SSD and RAM Upgrade Questions

bear with me, i don't know what i'm talking about lol

i have a lenovo legion 5 15IMH05H, 6GB NVIDIA GeForce GTX 1660 Ti graphics card, 8GB RAM (not sure what type), Intel(R) Core(TM) i7-10750H CPU @ 2.60GHz processor, UMIS RPITJ512VME2OWD SSD.

i would like to upgrade my RAM and SSD, but i don't know where to start, or what to buy that would be compatible with my laptop.

and would adding additional RAM and SSD erase what's already there? like would it overwrite what already saved/stored on my laptop?