Ok first off, im sure this has been asked many times before. I wont die if u dont answer it, it would just be better if u did. But is there any way to make a unit unable to be selected, like its part of the terain?

Place the unit as a sprite you mean? Like doodads?
Then place them as a sprite.
lol i dont know how.....

Well I use starforge for this. You can use SCMdarft too.
Just go in the layer box. Default should be Unit layer and select sprite and choose the unit you want to place. (Note I am not that sure about the differences about Unit sprite and just sprite. Don't really use them much.)
Thats how people make waterfalls, and other cool environments.
You can place many different sprites you see in-game, like the laser from nukes and even a starcraft cursor.
Just dont over use them.
ok i tried that yesterday, but i was still able to select it. I went to sprites then i placed it and i was still able to select it...

You may have placed it as a unit-sprite. Unit-sprites are more similar to actual units than anything else. If you're using Starforge, click the "mode" button until it says "Sprite" instead of "Unit." If you're using SCMDraft, select stuff from the Pure Sprites tree instead of the Unit Sprites tree.