Cannot connect to mySQL server.

I'm trying to set up opencart for my website, but when i fill in everything for the my sql database i get this error:

No connection could be made because the target machine actively refused it.

ive tried putting it on localhost, ive tried on 127.0.0.1. when i try on 192.168.1.126 (the database server) it says it cant find the database

the server hosting the php site is on 192.168.1.125

im very new to sql, i really dont understand it fully. im creating a new database in sql workbench. and filling in the info i need. How to i fix this error?

First of all, MySQL is deprecated, so use MySQLi instead.

So you have created a new DB at your server ?
You have created a User for the DB ?
... So you then have a Hostname and a Password for it.

Tip: recommended Collation is "utf8_general_ci"

Make sure the DB is empty of tables, then run the OpenCart installer.

Select "MySQLi" and enter your DB details.

It should work.
Good luck