What kind of framework, tools Should I use this app?

Hi guys.
I got an idea I think it’s cool.
Although I’ve never been a good programmer so far(almost starter), I’ve decided to learn how to develop applications and make my idea to reality on my own. (Of course, at some point, I’d need somebody else’s help like design stuff of sorts).
The problem is, I don’t know what kind of framework, tools I need.
Here are two main features I wanna develop

  1. AR app => user can see whether fashionable stuff like shoes, clothes fit their body over the phone through AR object. → Face, body tracking
  2. I wanna develop for Android and iOS. Preferably using the cross-platform.
    During my research, some people recommended Flutter + Firebase(Face tracking AI API), Flutter + Unity. On the other hand, Some told me don’t go for Flutter as I have to end up developing AR features for each OS(Android, iOS). Kinda confusing.
    I was going to develop this app using Unity + flutter, but I thought it would be a good idea to ask folks here before I decide what to do. Please consider I am not an experienced programmer. (it’s been just a few weeks since I started an AR app course with Unity on Udemy…) But I really want to give it a shot.

Any advice will highly be appreciated, guys.

You might want to ask this over in the AR forum instead of here. I’d also suggest asking a more concise question. For example, maybe focus on just the Unity + Flutter part. Or ask specifically about how to do face tracking in Unity. When you ask a question comparing two different approaches, the only people who will answer are those who’ve already used both, which is usually very few people, especially on a more niche platform such as AR. So you end up with no answers. Good luck!