You've uploaded screenshots only. Those screenshots appear as a slide when viewed.
You need to export your game from your software into whatever format it supports, or you prefer. For example, to play in a browser (html) or to download to play on a pc (.exe). Once you've exported the game, you upload those files onto itch.io for others to play.
If you tell us what software you're using, someone who knows that software might be able to help you with the next steps.
"Google slide" is not a game engine, it is a program to create slide-based presentations, where it is possible to extend the functionality through certain commands, which I imagine is how you created your "game".
It is similar to creating a game using a spreadsheet program, you cannot export a game, you can only save the presentation as a file, the problem is that the file can only be played using a compatible tool, that is, that person must download the file of your presentation, upload it manually to google slide or a similar program, such as office powerpoint and run it from there.
Just because it is possible to create something interactive with this type of program does not mean that you can create a game and expect it to be played on Itch, you will have to use a game engine.
Surely your game will be an interactive story or a kind of visual novel, if you have a PC, you can try Renpy.
If you don't have a PC and only have a tablet, you can try twine, it is an HTML engine for interactive text games (you can also use images) and it could work for you. There are many games on Itch based on Twine.
