I've watched You Tube but am still so confused.  First, I have no idea which hard drive I have now. All I know is it's not nearly enough room for what I need, so I'm quadupaling it.

Second, do I replace or add, or do I even have the option. I don't want to lose all my data. 

The installation part I think I've got, but my question is, if I am adding a 1TB SSD Crucial hard drive (the thin kind, not the box), do I need to clone my existing hard drive or will it all still be there since I'm adding, not replacing? If so, do I need a special cord or USB attachment? What if I have everything backed up to a recovery drive (USB) and on the cloud?

Please explain this to me like I'm a 5 year old. LOL.

Also adding 8GB ram to make 16 total.

This is what I purchased.

Crucial P5 Plus 1TB PCIe 4.0 3D NAND NVMe M.2 Gaming SSD, up to 6600MB/s - CT1000P5PSSD8

Crucial 8GB Single DDR4 2666 MT/s (PC4-21300) SR X8 SODIMM 260-Pin Memory - CT8G4SFS8266

Thanks in advance.

Ally