So I know a Portal game already exists but I wanted to make something fun.
Click to shoot portals, follow the tutorial, don't try to break the game it'll break very fast.
Press R to reset the room. Or the whole tutorial.
I'm glad to say the game didn't break. And I managed to beat the game!
The movement and projectile speed could use some tuning, and the music track gets on your nerves a little since it's so short. The puzzle elements like the glass and bouncy surfaces were neat. Also, I find it interesting that the "drop your block here" thingy can also move through the portal.
I was unable to progress into the game when I reached the level with the lasers. Is this what you mean with "easy to break the game"? It's easy to paint yourself in a corner that way.
Nevertheless, the idea is interesting. I think it would mostly needs polish: make sure you can get out of a situation where you are stuck (perhaps using a level select for screens you already beat). Also, after the tutorial I still had to find out several mechanics, like the "block goes here" (I could beat a screen without using it). I think getting stuck is my main issue, because it's the most off putting.
The walking is very annoying (with only "jumping" and having to not being able to keep the button pressed). It was also very finicky and hard to control the boxes and other objects. Furthermore, the music is very annoying as it repeats itself after about two seconds.