Thank you for your reply!

I actually ended up calling the number listed in the email and they told me that I didn't have any miles (besides the miles I received when I signed up) so there is no need to activate online service since I didn't have any miles to book award flights anyway. I let the rep know that I had planned to transfer miles from my bank but that I wanted to activate online service first so that I would be able to book a flight for my SO as well. He put me on hold while he consulted with someone and then told me to take a picture of my passport and take a selfie and email it to him. After that he was able to activate online service for me.

It's not clear if they would have automatically activated online service upon receiving the completed form if I had already transferred some miles over from my bank beforehand. At that point, I was just relieved that the rep was able to help me get it done so quickly.