Can GG make a RTS i need it for a proof of concept im working on, if it can then how do i go about it?

Not currently, no.

https://www.game-guru.com/features

"Real time strategy
Create more complex games that involve planning, manoeuvring, resource gathering and strategy"

It sucks this isnt implemented yet, thank you for your help.

I get the impression it could be done with a large amount of scripting. I've seen some folk around here do some amazing things with scripting.

There was an RTS creator floating around on steam but I think it's development has since been abandoned

Yes, I've seen a top-down simulation game done with GG thus I believe you could make an RTS. I would just need such an immense amount of work arounds and scripting that you'd be better off using different software.

(If someone knows the game I'm talking about, please link, I don't remember the name)

I've said it before and no doubt will again. Virtually any game is possible in Game Guru, if you can script. I've done a 2D shooter in the past, plus a Space Harrier type demo ( never released or shown it as it was unfinished, but the main engine worked okay ) I've even started a map editor in the past. An RTS in 2D would be possible (it may even be possible to use 3D in honesty). However, only if you can script it in it's entirety. You will be using practically no Game Guru features and everything would have to be controlled by you. So the answer is probably no - unless you can code an RTS in another coding language, in which case you can probably code it in GG.

I doubt this is ever something that will be "implemented" its more along the lines of something you'd have to figure out with scripting yourself. Game-Guru never advertised this type of play style so its undoubtedly going to be left in the hands of skilled LUA scripters.

This would require many overrides of the basic game mechanics. As there technically wouldnt be a player anymore and you'd be relying a lot on mouse coordinates. This would not be easy to implement i think for even those that are comfortable in LUA. While this is a very commonly requested feature i don't see it actually being implemented into the core engine as a "feature".