I would like to add columns to my google spreadsheet that I can edit

I have seen that this may be possible but I need a way to have a sheet that has all of the data that is coming in constantly and to be able to have columns next to that data that I can add information to and edit. 

I am booking flights for a large event and when I get someone's info I need to be able to use that info from the google sheet and next to it insert their flight confirmation number, etc.

Can you guide me in the right direction to maybe a tutorial or something that shows me how to do this?

First, you need to integrate Google Spreadsheet to your form by following this guide: https://www.jotform.com/help/228-How-to-Integrate-Form-with-Google-Spreadsheet

After that, open the Google Spreadsheet link and add the Text you want like Flight Confirmation Number, etc. Here's a screen animation guide that you can follow:

If you're referring to a different issue, please let us know. Thank you.