Probably not. Mindfulness meditation apps are fine. You could go to full-blown 2 hour long zazen meditation sessions multiple days a week, where you have the option of being hit with a stick when you start to lose focus/doze off; and you might gain some benefit from it. But unless that's something that seriously interests you, it probably isn't worth the considerable commitment.

There are all kinds of religiously inspired meditation practices, which are, again, probably fine if they're your thing.

Main point of any meditation that I know of, is cultivating awareness. You can do that in formal meditation classes, or you could do that while going fishing. It comes down to preference and perseverance.

Not really in terms of results . Best is to pick one you connect with so there is a chance you will keep doing it.

Not in the beginning. I recommend starting with any guided meditation with the focus on the breath. Then tweak what works for you: posture, counting or not counting the breaths, eyes open or closed, etc.