I changed the password to MYSQL because I couldn't remember the one I had before that was given to me by my old hosting and since then my hosting has been taken over by another hosting so I had no way getting the password...so I had to change all my passwords and because of it, my gallery no longer works: http://www.kristinkreukweb.com/gallery/
I know I can fix by doing it through install.php, but then I'll reinstall everything...which I don't want to do.
so I was wondering, how would I go about changing the password so the gallery can connect to database again.
Look in config.inc.php.
...which resides in the include folder on your server. Download the file to your client, edit it with a plain-text editor and re-upload it. Has been asked very often, please search before posting in the future.