u/Best-Recognition-528

I’m looking to add more RAM to my pc. This is a prebuilt, 4 slots, 2 are taken already. I’m going to be installing the stick myself. My question is; are there good video recs out there for me to watch on how to install? Should I just upgrade one instead of adding another? I’m really new to gaming pc/pc stuff in general and would just love a little help with it. Ty!