Either get an AMD Ryzen 5 2400G or 3400G and a b350 motherboard. start there and buy second hand rams and ssd/hdd if you can. Just buy the procie new and psu new so you have assuarance. you dont really need to get a gpu yet if you are not gonna play a graphic heavy game. if you are just gonna play Overwatch/League or minecraft you can buy the gpu later on. The average price for a 2400g pc with some second hand parts is 300-400 bucks. hope this helps