Though a 2GB RAM mobile is absolutely not sufficient for a tech savvy, it could be more than enough for somebody who likes to have a smartphone just for minimal purposes. That said, you can easily switch between PUBG and Asphalt 9 all day long with a nice 2GB RAM mobile.
If Amazon accepts your reason for the return, they give you a link to a UPS label. You take your item to UPS, they scan the label, and that is that. UPS will pack it and send it back to Amazon. Once your item is in the UPS system, Amazon will refund you money, either to your card or as a credit.
Vegeta was able to follow the fight by being able to sense the God power. He had every credit to become the God himself in the original situation but Goku wanted the fight. Vegeta was the only other full blooded Saiyan known left in the anime during Goku's power up.