wanting to build a new pc and interested in this processor but i've heard some rumors of it hitting really high temps

any truth to this rumor or can I work around it somehow?

I don't understand the question or your concern.

The AMD Ryzen 5800X doesn't come with a stock cooler like the 5600X or the previous generations before the 5000 series. So you'll need to buy a separate cooler, which should be better than the stock cooler. Whatever cooler you're interested in buying, will show some sort of compatibility or rating against a particular CPU. So just go to the manufacturer's site and see if 5800X is listed there as part of the cooler's specifications.

Any truth to what rumor? CPUs in general, will get hot under heavy load.

Can you work around it? Yea, cool them down, preferably with a CPU cooler.

Here is 5800x underwater and underload. Does this answer your question?

HWINFO64>

This series of ryzen does run warm. But I have a 5800x and it’s fine

No issues with mine either, go get one