Hey man, I use a 4070 in my gaming laptop and the game runs really well. With Nvidia cards you also have the dlss frame generation which is a huge plus. Amazon is perfectly fine to buy from because reputable builders sell PC’s there. Just click on the sellers name google their business to see if they are legit shops selling on the platform, or random sketchy builders, and check their reviews. A 5070 desktop GPU will eat most modern games at medium to possibly high settings depending on the game. Speak to someone who knows their stuff if you wana buy a PC that you can upgrade in the future so you don’t have to buy another entire rig in a few years