Even though I'm still learning English…, I want to study Spanish too.

I want to try to study Spanish too.

It would be better to make this one sentence.

However, I'm struggling to create English sentences and I can’t alsoalso can't speak English.

But!!!!!

But I’ll do my best.

This app starts with simple sentences, not words like "morning" or "water"," so I’m not sure which word is which part of speech unless I check.

First of all, I’m going to memorize there phrases and I’ll keep studying it little by little.

First of all, I’m going to memorize theire phrases and I’ll keep studying it little by little.

Even though I'm still learning English…,

An ellipsis is generally only used at the end of a sentence. It can sometimes be used in the middle for the effect of making it look like you're pausing, but it is never used with another piece of punctuation.

However I'm struggling to create English sentences and also I can’t also speak English.

The position of "also" here is a little hard to explain but if you say you "can't also do something" then it gives the impression that you can't do that something at the same time as something else.
For example: "If I'm running, I can't also sing." - this tells the reader that the writer cannot both sing and run at the same time. They might be able to sing if they're not running, but they can't do both together.

But!!!!!

This isn't strictly grammatical but it does feel natural for a more casual piece of writing so I won't write any correction

I’ll do my best.

This is grammatical, but in English this feels like the sort of thing you'd say at the end, rather than in the middle of your writing.

First of all, I’m going to memorize there phrases and I’ll keep studying it little by little.

It's possible you wanted to say "their" instead of "there". These are commonly mixed up. I'd say here "the" feels the most natural, however. You've referred to the phrases in the previous sentence, so it's clear which ones you mean.

Even though I'm still learning English…,

'...' and ',' are both fine there, they both signal a pause in speech (the nuance is that ... is a longer kind of pause)---the only thing to avoid is having both of them there at the same time.

However, I'm struggling to not only create English sentences and I can’but also speak English.

"not only..." helps when you're introducing more than one negative thing at the same time, the "not only" signals to the listener there's something else to hear from you.

First of all, I’m going to memorize theire phrases and I’ll keep studying ithem little by little.