will the game be only released on steam or also here or on gog?
Yes, it will absolutely be released on steam and other platforms as well if people ask for it. In fact, the Steam page is currently being reviewed and I expect it to be up in a 2-3 days or even earlier. The steam link is in this page, below, and it will be accessible shortly, feel free to wishlist it there if you like. The full release will probably be around August/September.