I have 4 of these that i plan on using as a hedge but i don't know how far apart to plant them since im clueless as to how large these things can get.
It's hard to be certain of variety because there are so many which have been created in the last few years, but whichever variety it may be, its definitely a prostrate one, evidenced by its growth habit. If you only want a low hedge, it'll be fine, but it is likely to remain up to about a foot high for the next ten years, possibly reaching 1-2 feet at maturity, with a spread sideways of between 4-6 feet.
Prostrate junipers like this are not ideal as hedges because their growth habit is to sprawl outwards, though they do make useful ground cover; any pruning should be restricted to once a year, and even then only a light prune, so if you wanted a more formal, higher hedge, this is not really a suitable choice.
The most similar variety I know of without trawling the internet for hours is Juniperus communis depressa aurea https://plants.ces.ncsu.edu/plants/juniperus-communis-depressa-aurea/