I don’t think anyone uses Gimp for painting or drawing. It has the filters and extensions and tools which make it useful for cleaning up or editing photographic imagery.

If I’m looking to paint or draw, I fire up Krita, not Gimp.

There’s Darktable for handling photos, as well, but that’s an alternative for Lightroom, not Photoshop.

Good news, the GNU Image Manipulation Program is designed for manipulating photos

GIMP and darktable work well for photo editing.