I need to put my irs pin number in but I file my taxes Before I could hit it in can I go back and pick it in

You will have to wait for the IRS to either Accept or Reject your filed federal tax return.  Since you received an IRS 6 digit IP PIN, the IRS will more than likely reject your tax return.
If the return is rejected you can make the necessary changes and e-file again.

To enter, edit or delete a 6 digit IP PIN

Click on Federal Taxes (Personal using Home and Business)
Click on Other Tax Situations
Scroll down to Other Return Info
On Identity Protection PIN, click the start button

If you already submitted your return, and you have an IP PIN that you need to enter, your return will be rejected.  When it is rejected you can enter it then.

If you did not yet submit your return, you will simply need to select the following and enter your IP PIN

• Federal
• Other Tax Situations
• Start next to Identity Protection PIN under Other Return Info

If this is just the regular 5 digit pin it asks for and not the IP PIN the IRS issued to you, then you can just go back through the file section and enter your 5 digits.