Gimp is pretty good and considering that it’s free, it’s pretty spectacular.
If you want something more photography oriented I recommend DarkTable which are sort of comparable to Lightroom .
Darktable is similar to Lightroom in use case, and GIMP is similar to Photoshop.
Given that for most photo editing you want Lightroom, not Photoshop, you probably want Darktable, not GIMP. I have very limited personal experience with either.
more free photo editing programs here: https://www.xp-pen.com/forum-1790.html