Inkscape (2D) is free and a powerful vector program
Fusion 360 (3D) is free if you’re a hobbyist and not a store
I use Paint . net (2D) for my raster stuff
Affinity Designer gets a lot of love on these forums 
Honestly, I’d go check out some of the tutorials on the individual programs and see if some make more sense than others. So much of finding the right program is finding the one that was designed by people whose brains work like yours! I, for instance, was never able to use GIMP successfully despite it being a great program 