My opinion is that learn letter and grammar at the same time. if you still don't remember all hiragana, learn 5 letters every 3 days and use these hiragana from next time instead of Romaji. it is not really necessary to remember katanaka and kanji at the beginning but hiragana is important to understand the way to pronounce. but also learning only letters is sounds so boring and why don't you do it at the same time :) Don't forget that the most important thing is enjoy learning Japanese :) Good luck!

First of all, you need to be able to read hiragana and katakana, as Hakon said. I would recommend that you should learn everything. Japanese grammar, pronunciation, and making conversation, these skills are connected. In my opinion, being able to read hiragana and katakana is the first thing you should do. Well, it seems to me that you are doing well, as I can see your notebook. keep going :)

I'd advice you to learn hiragana and some katakana as fast as possible, and then learn kanji as you go along. Of course, you need to know some basic grammar and vocabulary to get started writing in hiragana in the first place, but the sooner you just bear down and memorise those syllables and signs, the easier it'll be! More importantly though, everyone learns differently, so if you try learning hiragana, but find that you'd like to know some more grammar first, go for it! The only important thing is that you keep studying! がんばって！