To scan a mountain using the photogrammetry process, you need 3 things: a camera, a way to fly around the mountain, and software to process the photos. A drone makes the first two achievable and the options for processing the photos are more accessible than ever before.
Hike up a significant portion of the mountain. Whether or not you go to the tippy top depends on how you want to fly your drone. If you choose to fly manually, you won't want to lose signal when your drone is on the backside of the mountain. If you fly an automated mission, you'll want to be high enough from launch that the parameters will match up with the mountain peak in frame.
For southeast Alaska, you'll want to consider the weather conditions. For an artistic capture that shows the mountain in all its glory, you'll also want a touch of seasonal snowfall and the idyllic solar angle.
It's best if you can fly high enough that the drone looks down at the mountain. If you are eye-level with the peak, the background will have too many features. Some software can mask the subject, so this isn't as much of an issue as it was when I developed these habits.
After all else is considered, fly around the mountain taking many overlapping photos. At minimum, fly a circle around the mountain taking a photo every 10 degrees, 36 photos. In many ways it is better to have more photos, but also consider that clouds can form or obscure the scene suddenly. Shadows will shift during a very long photoshoot. The best subject for photogrammetry is one that doesn't move or change throughout the duration of the scan.
Once you're ready to process photos you can either go with an app on your phone like PolyCam that will upload to the cloud and process on their servers. Or you can use something like OpenDroneMap or Meshroom and process on your laptop or desktop. Other software is available, though I don't know enough about them to write anything.