Can I pay some of my credit card off before 1st bill generation?

Sparx

The short answer is, you can pay whatever you want, whenever you want off the card - as long as it's by the due date and covers at least the 'minimum payment' on the statement.

Just always remember you need to make the min payment or more after a statement has been generated, before the due date.

Answering your original question, As your first statement hasn't been generated, you will need to make another payment by (or before) the due date again, after the statement has been generated...