/3/ - 3DCG

>>729397
>>729398
I don't know what they/you were thinking with your unwrap to be honest, but here's how I would have done it. N-gons or not.
The main structure can be unwrapped straight up without any seams. Just look at it from the front, and project from view. You won't have any seams, or stretching that way. I don't know if there's a back side or not, but in the same case, it's fine to have them overlap if they're going to be the same texture/material or if you won't see it.
The posts or whatever can just be unwrapped like a basic cylinder. Seam around the top face, then one down the side. I'd just unwrap the tops of them separately and have them as they come out (pic related), so they get textures on the inside side faces without any extra work. Blender is a little weird unwrapping cylinders though, so make sure to be in front or side view (in orthographic) before you unwrap it.
Overall it's a super simple shape to unwrap. Even to make. I don't know what's up with that geometry to begin with. Shouldn't need N-gons at all, and even if it did, it wouldn't make much difference when unwrapping. UVs don't care about that. And if it's not gonna deform like a limb, or be subsurfed, n-gons don't really matter. Especially on flat objects.

As far as learning UVs goes, I go through how I conceptualize it here >>728288
Basically, imagine you can cut up the object with magic scissors to make it lay flat on a table. The seams are where you would cut it. If a part can lay flat on its own, don't cut it up. There's a bit more advanced concepts that go along with it, but it's enough to get started on. You'll pick up when and where to cut things with practice and it'll come naturally.
Hope it helps.