Increase file size uploads - for non technical people

I’m basically just a windows PC user who wants to increase the file size on our HOA website. I see the limit is normally 512 mb.

Is there a way to do this without getting into the coding?
I saw some references to PHP and editing files which I may be able to do. But how do you connect the PHP software to get to the lines to edit?

Thanks, would appreciate any advisement you can offer.