Yes you can. By default if you have created and "Invite" email template, the RSVP button will be position at the end of your email content.
However, we also allow user to position the RSVP button anywhere in the invitation email template.
To add the RSVP button anywhere in your email invitation template you can go to the email editor, and look for "Insert Tag" drop-down at the editor menu.
Please make sure that the email template is "Invite"
From the drop-down you can choose "RSVP Button"
If you would like to edit the color or the text of the button you can head to Event Details >> Setting >> RSVP Option