I want to start in bitcoin and I have made my wallet.
Do I have to get a bitcoin paying job or can I use my fiduciary shitcoin to get some bitcoins?
By fiduciary shitcoin, I think you mean fiat? Right? If that is the case then you can easily create an account on coinbase and transfer your dollars into your wallet and use it to buy any amount of bitcoin, then transfer it to the private key wallet that you have made. Private key wallets are different from exchanges they won't allow you to exchange your crypto for fiat, so you can't buy using wallets but you can eventually send bought bitcoins into these wallets. Another method obviously is to get a bitcoin paying job and this money you can directly receive into your wallet so no need to exchange anything. Alternatively, if fiduciary coin is some altcoin which I am unaware of, you can use Changelly or other exchanges that have this coin listed to sell it off.
