Answer 1

Depends a little on what kind of database. I assume it’s SQL.
Anyway-
You need to set up a server something like Apache server. You can find out with google how to get things going.

You will also need to use a server side script. Something like PHP.

So your webpage will send data to the server which uses the server side script to access your database and then send a response back to your site.

Not sure if that’s really what you’re looking for but there’s no other details in your question.