Child theme, best way to

Hi,

I’m working on a child theme. For the modifications, i want to know what code the parent files have. Where can i best access these files?

Example: I have the child theme as my mainwebsite. I now want to make a style.css modification, but first i want to go look in the parent style.css. Also, i would want to look into every other code, like footer and header.

Right now, what im doing is i reload the parent theme on my website, then access wp-admin/theme-editor.php and look for the codes. After that i load my childtheme back and edit.