Hello @umarbuilds
It looks like you did everything correctly the only actual issue is the database name mismatch.
Your Bagisto installation is trying to connect to:
bagisto_db
But on your hosting panel, the real database name is something like:
bagisto_db-xxxxx (with an auto-generated suffix)
Because the DB name in .env does not match the real one, MySQL rejects the connection, which triggers the HTTP 500 error.
Kindly let us know if you have further queries.
Regards