How do I make a reservation for a proxy session?

Just type Ogden Utah temple in your Google search. Click into the website. Then across the top you will see some options. Click on attending the temple. It will prompt you to sign in to your account and then you can make an appointment.

Yes

Also, if a month has no availability, click to the next month... then back to the previous month and more spots might open up (I've done that 4x in the last couple of months). I've been able to schedule multiple appointments a month (endowments, baptisms) at the various temples in Utah.