Welcome to the forum from the beautiful woods of Maine!
There’s many knowledgeable members here who are willing to help you with any questions you might have. Search the forums using keywords and if you don’t find an answer, post your questions...
You are only exempt from registration if you are flying only for recreational purposes and flying a drone under 250g. Selling photos is not for recreational purposes. You need a part 107 license and to register your drone.