If you feel like you can think clearly and are questioning if you are dreaming but are unsure, you are not.
All methods of lucid dreaming aim at making you think clearly and question if you are in a dream. With that thought, it should be quite obvious to confirm you are in fact in a dream. Dreams are really not that good, sleeping is just kinda like a heavy suspension of disbelief.

Yeah. It is not like you can perfectly recreate them, but as long as you don't see a problem with whatever your brain fabricates it's not gonna do anything.

What I used to do was try to breath through my nose. That is a different mechanism, where probably for safety your body doesn't "disconnect" your breathing. If you hold your nose shut, you will still be able to breathe in a dream.
It is something you can easily make a habit, as just quickly pinching your nose doesn't look weird, and then you will naturally do it in your sleep too and become lucid.

All you really need is a moment of doubt, and if you have experienced a few dreams you will always be able to tell if you are dreaming or awake at a thought, at least in my experience.

I have stopped lucid dreaming a while ago, but I think I am still always aware when I sleep based just off of how I sleep. Ever since then it feels more like I am just going along with my dreams most of the time, and occasionally I just decide a nightmare sucks too bad and change it or wake myself up.

Look at text. Look away. Look again. Are the words the same? In a dream, they sure as fuck won't be.

I think the idea is to build a habit of checking, so you don’t even need to have that “hold on, am I dreaming?” moment. You just habitually do that thing you always do, and then “oh it seems I’m dreaming. I didn’t notice”