Can you set the M.2 SSd card in your BIOS for Data File Storage?

So I had a gift from my uncle recently and it was a Samsung 970 Evo 1 TB.He told me that to put in that SSD as Raid 0 (or something like that). He didn't gave me much details, maybe he did but just didn't understand the language of a Computer Engineer. He said to make the booting of computer and apps fast.But, the thing is, my uncle didn't know that I have another 970 Evo 1Tb on the way for the pc I'm about to build. And here's my plan.

One of the M.2 SSD will become for the "Speed Thingy"And the other will be for storage for my files, video editing project, etC.My question is, because i watched some vids, read some feeds already about the BIOS thingy which is the gateway to set (or program? Whatever that is) the M.2 ssd as your "Boot drive" but IS IT ALSO POSSIBLE TO MAKE THE OTHER M.2 FOR YOU DATA/FILE STORAGE?cuz i can't afford to buy HDD (not a fan of brick looking storage anyway)Or the SATA 3 SSDs. Put all my budget for that 970 of mine.