Grammar & sentence help?

Hi friends!
I just started learning Japanese about a month ago, aside from picking up little things here and there from years of watching subbed anime.
My main goal for learning is to be able to hold conversations with some of my native Japanese friends.
So far I’ve managed to learn all hiragana (with a few slip ups but I’m working hard to keep them in my brain lol), most katakana, and very minimal kanji.

I’m looking for tips on how to read & form sentences. I’ve learned of a few particles such as ga, wa, ni, o, do. But to be honest, I’m having a hard time remembering which context each are used in. Wa is easy for me, for the most part it comes after talking about either myself or someone else as the subject. But the rest I can’t seem to remember.

I’m currently using the HeyJapan app to learn, which has been helpful to some degree, but I find that there isn’t enough repetition and its very fast-paced between topics.
Any tips on reading, writing & speaking sentences would be greatly appreciated! Feel free to recommend apps/other resources that can help as well!