Why can I no longer go to file and open a new window so I can cut and paste info from one estimate to another anymore.???

Good day, Support10.

I'd like to know more about this. Did you migrated from QuickBooks Desktop to the Online version?

If so, the feature to open multiple windows is only available in the Desktop version. You'll be unable to copy and paste info from one estimate to another in QuickBooks Online.

You can check this helpful article on how to use estimates/quotes in QuickBooks Online. 

If you have more questions, please leave a comment below. Have a nice day!