Of course you can. You can do just about anything here so long as your following procedures and doing it just in the board it was meant for.

If you want to do some promotion, the gambling board is there for you if it’s a crypto gambling project, you can announce your thread there. You also have the service board to run a campaign and maybe announce your product. The service discussion board is also there for you to utilize and also, the bounty section. You just evaluate what you want to bring to the public and see where it suits for placement.

A note to do is,
Trying to post links to your project anywhere you make comments, it’s not a very patronized idea here. A few times when it’s necessary might be over looked but, making it a culture just to get more clicks found even get you nuked.