Some years ago I had similar motivations to you. I had been out of photography for years and thought digital would be fun. It is impossible to tell you what camera to get, and would spoil the fun of discovering this for yourself anyway. However, based on personal experience, and learning I will tell you things NOT to do:
1) Don't buy a camera because you were told to.
If you wish to get a question removed from this SE site, ask for advice on what camera to get. This opinion based, and the only one who can answer the question is you. It all depends on budget, needs, wants, preferences, etc. Best bet is to find what others near you use, and try theirs out for a few hours. Or better yet, rent a camera and lens for a week and use it.
2) Don't buy a brand because you used to own one
Cameras have changed much since the digital revolution, with some vendors emphasizing different aspects that were no relation to their emphasis in the film world. Also, consider the system: all the lenses, flashes, and compatible gear. Try everything and be open to anything.
3) Don't buy a brand because you have a few old lenses
Chances are, if you had a camera before, and were not really into photography seriously, you had a kit lens or two and were perfectly happy with it. For some systems, these lenses may no longer work or likely will be of too low a quality to be of value as you grow in your needs. Unless you bought top of the line lenses, assume you need to buy new lenses as well, regardless of the system you buy.
4) Don't assume you will sell any photos.
This seems to be a frequent motivation, and it sounds reasonable: post some images online and wait for the buyers! Instead it is better to think of it this way: you will likely sell as many photos as you have personally bought. Unless you are going to go into wedding photography or portrait business, your random photos, regardless of quality, are not going to sell. Rarely do people simply want to buy photos. If there is an event, or their family in the photo, then you may sell a few. Plus consider the competition: its easier to go to a stock photo house or pull an image off Flickr for free.
In any case, enjoy your re-discovery of photography. Research, learn, try, test and enjoy the adventure of learning new concepts. Go out and shoot photos and learn what makes sense to you, what is best for your style and be open to getting the gear that works for you.