It's highly recommended that you transfer the coins to your other account(s). But if you want to use that brand new account and change account info for PSN, here's how you do it:
1. Go to Settings on your PS4.
2. Select PSN in the settings list.
3. Select Account Information.
4. Here you can change your email address and password. If you don't know how to login to PSN with your brand new account, Click Here to check.