Hey there! It looks like you used scratch for this, this proves that i can make a game via scratch! also, nice game!
If you want to export and publish to itch.io, export it to HTML. I would recommend 60 FPS, with a custom loading screen, and the resolution that you prefer. If you want the player's save data to be saved correctly (if it needs to), create variables in the cloud, and then in the packager page, select the advanced variables mode and select the variables you prefer as "Store in local storage" and cloud variables such as high scores, put "Connect to cloud variable server". There are some additional settings such as the cursors, I use the function of not showing cursors, since I have a character that follows the mouse position even if it is not seen, and thus I can have several cursors at the same time. I would not touch the other settings, they are for very advanced projects. I hope you find it useful!