I have struggled with PS at times but I will get there
Best way to start learning, is to use a photo you like, if you have the new version ps, (which is subscription based
) you are able to delete all backgrounds easily, but, before I started to pay for it, I was using cs6 which you can delete backgrounds but have to do it manually, in the end, you can add wallpapers background themes to the photo to make a whole new photo, I started off learning ps with using old greyscale photos my great great grand parents and put them into color images
But if your into art work, if you going to ps then I do recommend that you use a tablet, not an expensive one with screen just normal graphic tablet and pen, makes ps even better its just like drawing on paper