How can I receive the submissions in all caps?

You can do this in the form email template, but not in the actual form and submissions page. The output depends on how the user input the data in the form fields before submitting.

To change the texts in all caps in the email template, you just need to add an inline style to the question/answer table. Just click the Source code icon:

Find the question/answer table codes and add style="text-transform: uppercase;"

The result in the email will be like this:

I hope that helps. Let us know if you need further assistance.