DBA - Server / Instance Level:

 --https://www.datavail.com/blog/scripting-out-the-logins-server-role-assignments-and-server-permissions/

/********************************************************************************************************************/
-- Scripting Out the Logins, Server Role Assignments, and Server Permissions
/********************************************************************************************************************/
SET NOCOUNT ON
-- Scripting Out the Logins To Be Created
SELECT 'IF (SUSER_ID('+QUOTENAME(SP.name,'''')+') IS NULL) BEGIN CREATE LOGIN ' +QUOTENAME(SP.name)+
			   CASE 
					WHEN SP.type_desc = 'SQL_LOGIN' THEN ' WITH PASSWORD = ' +CONVERT(NVARCHAR(MAX),SL.password_hash,1)+ ' HASHED, CHECK_EXPIRATION = ' 
						+ CASE WHEN SL.is_expiration_checked = 1 THEN 'ON' ELSE 'OFF' END +', CHECK_POLICY = ' +CASE WHEN SL.is_policy_checked = 1 THEN 'ON,' ELSE 'OFF,' END
					ELSE ' FROM WINDOWS WITH'
				END 
	   +' DEFAULT_DATABASE=[' +SP.default_database_name+ '], DEFAULT_LANGUAGE=[' +SP.default_language_name+ '] END;' COLLATE SQL_Latin1_General_CP1_CI_AS AS [-- Logins To Be Created --]
FROM sys.server_principals AS SP LEFT JOIN sys.sql_logins AS SL
		ON SP.principal_id = SL.principal_id
WHERE SP.type IN ('S','G','U')
		AND SP.name NOT LIKE '##%##'
		AND SP.name NOT LIKE 'NT AUTHORITY%'
		AND SP.name NOT LIKE 'NT SERVICE%'
		AND SP.name <> ('sa');

-- Scripting Out the Role Membership to Be Added
SELECT 
'EXEC master..sp_addsrvrolemember @loginame = N''' + SL.name + ''', @rolename = N''' + SR.name + '''
' AS [-- Server Roles the Logins Need to be Added --]
FROM master.sys.server_role_members SRM
	JOIN master.sys.server_principals SR ON SR.principal_id = SRM.role_principal_id
	JOIN master.sys.server_principals SL ON SL.principal_id = SRM.member_principal_id
WHERE SL.type IN ('S','G','U')
		AND SL.name NOT LIKE '##%##'
		AND SL.name NOT LIKE 'NT AUTHORITY%'
		AND SL.name NOT LIKE 'NT SERVICE%'
		AND SL.name <> ('sa');


-- Scripting out the Permissions to Be Granted
SELECT 
	CASE WHEN SrvPerm.state_desc <> 'GRANT_WITH_GRANT_OPTION' 
		THEN SrvPerm.state_desc 
		ELSE 'GRANT' 
	END
    + ' ' + SrvPerm.permission_name + ' TO [' + SP.name + ']' + 
	CASE WHEN SrvPerm.state_desc <> 'GRANT_WITH_GRANT_OPTION' 
		THEN '' 
		ELSE ' WITH GRANT OPTION' 
	END collate database_default AS [-- Server Level Permissions to Be Granted --] 
FROM sys.server_permissions AS SrvPerm 
	JOIN sys.server_principals AS SP ON SrvPerm.grantee_principal_id = SP.principal_id 
WHERE   SP.type IN ( 'S', 'U', 'G' ) 
		AND SP.name NOT LIKE '##%##'
		AND SP.name NOT LIKE 'NT AUTHORITY%'
		AND SP.name NOT LIKE 'NT SERVICE%'
		AND SP.name <> ('sa');

SET NOCOUNT OFF

 

Database / Object Level:

USE Master  -- Use the required database name here
GO
SET NOCOUNT ON;

PRINT 'USE ['+DB_NAME()+']';
PRINT 'GO'

/********************************************************************************/
/**************** Create a new user and map it with login ***********************/
/********************************************************************************/

PRINT '/*************************************************************/'
PRINT '/************** Create User Script ***************************/'
PRINT '/*************************************************************/'

SELECT 'CREATE USER [' + NAME + '] FOR LOGIN [' + NAME + ']' 
FROM sys.database_principals
WHERE	[Type] IN ('U','S')
		AND 
		[NAME] NOT IN ('dbo','guest','sys','INFORMATION_SCHEMA')

GO
-- Troubleshooting User creation issues
PRINT '/***'+CHAR(10)+
'--Error 15023: User or role <XXXX> is already exists in the database.'+CHAR(10)+
'--Then Execute the below code can fix the issue'+CHAR(10)+
'EXEC sp_change_users_login ''Auto_Fix'',''<Failed User>'''+CHAR(10)+
'GO **/'

/************************************************************************/
/************  Script the User Role Information *************************/
/************************************************************************/

PRINT '/**********************************************************/'
PRINT '/************** Create User-Role Script *******************/'
PRINT '/**********************************************************/'

SELECT 'EXEC sp_AddRoleMember ''' + DBRole.NAME + ''', ''' + DBP.NAME + '''' 
FROM sys.database_principals DBP
INNER JOIN sys.database_role_members DBM ON DBM.member_principal_id = DBP.principal_id
INNER JOIN sys.database_principals DBRole ON DBRole.principal_id = DBM.role_principal_id
WHERE DBP.NAME <> 'dbo'

GO

/***************************************************************************/
/************  Script Database Level Permission ****************************/
/***************************************************************************/

PRINT '/*************************************************************/'
PRINT '/************** Database Level Permission ********************/'
PRINT '/*************************************************************/'

SELECT	CASE WHEN DBP.state <> 'W' THEN DBP.state_desc ELSE 'GRANT' END
		+ SPACE(1) + DBP.permission_name + SPACE(1)
		+ SPACE(1) + 'TO' + SPACE(1) + QUOTENAME(USR.name) COLLATE database_default
		+ CASE WHEN DBP.state <> 'W' THEN SPACE(0) ELSE SPACE(1) + 'WITH GRANT OPTION' END + ';' 
FROM	sys.database_permissions AS DBP
		INNER JOIN	sys.database_principals AS USR	ON DBP.grantee_principal_id = USR.principal_id
WHERE	DBP.major_id = 0 and USR.name <> 'dbo'
ORDER BY DBP.permission_name ASC, DBP.state_desc ASC


/***************************************************************************/
/************  Script Object Level Permission ******************************/
/***************************************************************************/

PRINT '/*************************************************************/'
PRINT '/************** Object Level Permission **********************/'
PRINT '/*************************************************************/'

SELECT	CASE WHEN DBP.state <> 'W' THEN DBP.state_desc ELSE 'GRANT' END
		+ SPACE(1) + DBP.permission_name + SPACE(1) + 'ON ' + QUOTENAME(USER_NAME(OBJ.schema_id)) + '.' + QUOTENAME(OBJ.name) 
		+ CASE WHEN CL.column_id IS NULL THEN SPACE(0) ELSE '(' + QUOTENAME(CL.name) + ')' END
		+ SPACE(1) + 'TO' + SPACE(1) + QUOTENAME(USR.name) COLLATE database_default
		+ CASE WHEN DBP.state <> 'W' THEN SPACE(0) ELSE SPACE(1) + 'WITH GRANT OPTION' END + ';' 
FROM	sys.database_permissions AS DBP
		INNER JOIN	sys.objects AS OBJ	ON DBP.major_id = OBJ.[object_id]
		INNER JOIN	sys.database_principals AS USR	ON DBP.grantee_principal_id = USR.principal_id
		LEFT JOIN	sys.columns AS CL	ON CL.column_id = DBP.minor_id AND CL.[object_id] = DBP.major_id
ORDER BY DBP.permission_name ASC, DBP.state_desc ASC



SET NOCOUNT OFF;