There 2 ways you can do that;
- You can make the game playable on the game page. It requires a few steps, but it will make the game playable in the browser as it does on Flowlab. Anyone is able to do this, I have instructions on how to do this here or with the link below.
- Or if you have indie, you can export your games in a zip file that can be uploaded to the site. They would have to download the game to play it. You can also sell the zip file on itch.