Yeah, I don't know what happened with my fingers there. I'm still learning the layout but having the first two letters you taught on the index fingers made those easy to learn to type. I even chose ت for the example specifically because it's the same key as ـ and I am super lazy efficient when it comes to typing. However, I do remember I didn't make the text nice and big first; at the normal size, without the other alongside for comparison, ت ن .
It's right in Anki, though. One of the other advantages of custom notes is editing the styling so the letters are literally ten times as large. And if it had been wrong, a single correction would have fixed all eight cards.
I might know what you mean. My brain likes to play hide the dictionary, and at those times there's just no link between word and meaning. I can even repeat what I've heard, or read out writing, yet still have no idea what I'm saying. If I'm trying to talk at the time, I just stop and point or mime for a bit. And I could never take notes in class, because I had to keep concentrating on what I was hearing.
But onto the good news (maybe). If your issue is language-independent, then your target language being very different might not be such a problem. The differences might even be helpful.
I started learning Japanese last year. I actually wanted to learn Mandarin but, also like you, the thought of processing the tones put me off (at the time). I thought, though, that if I start with the alphabets and the kanji and focus on reading first, then I'll have plenty of time to get used to the sounds, and since the kanji are in large part derived from Chinese, I'll have a head start when I switch targets later. I've accepted that I might never be a great conversationalist—I'm not in my first language either—but I fully intend to at least be a competent reader and writer, which is more transferable to Mandarin, I think, since the meanings seem to be more preserved than the pronunciations.
Right now, I'm still on target to finish the 2000-ish regular-use kanji in June. While I study those, I listen to Japanese songs which I've found the lyrics and their translations for. I keep them in my playlist until I know every word, which provides a kind of precognition of what comes next that doesn't always exist in conversations. At first, it was only Yoasobi and Riria that had clear enough singing for me to follow along, but over the hundreds? of hours of listening, my brain's definitely developed because I can manage quite a few others too now.
Something clicked about a month ago where everything started feeling easier. Not quite just easy (yet?) but definitely markedly less difficult. I wasn't expecting that. I never got that with the 6 and 9 years of other language learning in school, but then I've probably put more into this than school provided for those. I'm not going to patronisingly say that if I can do this then you can too, because I don't know how we differ, but I will suggest that maybe you're being a little pessimistic about paths you haven't fully explored.
That confidence boost I got made me rethink the Chinese tones. Of the videos trying to explain it, I found Mandarin Chinese TONES GUIDE That Schools Don't Teach You the most helpful. I haven't had the time to really practice, but since last year I've gained the belief that it's not some impossible hurdle. It is going to take a lot of listening to get there, though.
So I suppose what I'm saying is give it a try because you won't really know until you've given it a really good go, and don't use school experience as the basis for judgement because you can set yourself a very different curriculum.