is a physical hardware component. It is a set of microchips soldered onto a stick of circuit board that plugs into your computer's motherboard. Because it is physical matter, you cannot download it any more than you could download a bigger battery for your phone or a faster engine for your car.
If you have an old PC with an HDD, you can plug in a fast USB flash drive and use it as a cache via Windows ReadyBoost. It’s not a RAM replacement, but it helps with system snappiness. How To Download Ram For Free
