It looks like you have a mysqli connection, but the code on the page is all standard mysql. The connection file has to match the code. I think your best bet is to delete this connection and create a new one with the same name. Make sure it is a regular mysql connection and not a mysqli connection. Then you will have to make sure that your web server is running php6 or earlier (not php7), but based on the errors you were getting I think that isn't a problem.