I have a stock Specialized Rockhopper Pro (2018) and I want to upgrade the bars and stem. Bars are too short (720mm), not enough rise (10mm), and the stem is too long (90mm).
I know as far as bars are concerned I'd like 760mm and at 20-30mm of rise. Stem not sure, but definitely shorter than 90.

I'm pretty clueless when it comes to MTB part manufactures/models. So any help would be appreciated.

How much are you looking to spend? I recently bought a Renthal CF Fatbar that I like. If you only want 760mm wide, they offer a more XC oriented one that I think comes in that width.

But truthfully a CF bar from any reputable company is probably fine.

Probably the biggest difference between different brands is the upsweep and backsweep.

As far as stems, as long as it has a 4-bolt faceplate and the length/rise I want, they are all pretty much the same to me. I don’t really see the point in CF for a stem. I look for something on sale, as I sometimes end up going through a couple to find the right length.