Migrate SQL Server database with instance level logins
There are some fantastic Powershell scripts located at dbatools.

You could use Copy-SqlDatabase to migrate your databases.

Then, you could take advantage of Copy-SqlLogin by generating the Powershell commands via T-SQL script for the logins you're interested in.

select 'Copy-SqlLogin -Source sqlserver -Destination sqlcluster -Logins ' + name + '' from sys.database_principals where type_desc='sql_user'


After migration, make sure you take care of orphan users.  You could use something like this:

declare @cmd varchar(max)=''
select
    @Cmd=@cmd + 'ALTER USER ' + dp.name + ' WITH LOGIN = ' + dp.name + ';' + char(10)
from
    sys.database_principals dp left join
    master.sys.server_principals sp on
        sp.name=dp.name
where
    dp.type='s' and
    dp.default_schema_name&lt;&gt;dp.name and
    sp.name is not null
order by dp.name
--print @Cmd
exec (@cmd)