u r thinking too much ahead of ur age. if u need to buy games on steam, trade same amount from ur pocketmoney with ur parents and ask them to pay in steam.
if u want to open a bank account, open it in some govt bank, that has less minimum balance requirement. it has to be a joint account with either of ur parents, and u can use it to save a fair percent of ur pocketmoney on regular basis.
to tell the truth, if i had a 16 yr old kid asking in internet about how to get a cc, i donno what i would have done..... jumped from window may be ?