Once you have basic grammar understanding, the next step is to start reading. Except, it’s not really reading at this point in your learning. It’s more a matter of deciphering. You’ll encounter a lot of unknown grammar and you’ll need to look it up and learn it. Most words you encounter you won’t know and you will have to look those up. It won’t feel like reading at all for a while.
Over time, the pattern recognition machine known as the brain picks up on seeing the same grammar in different scenarios, and gets better are recognizing it. It takes time, but slowly you get better at recognizing the grammar as you’re reading. You still have to look up a lot of words, but it starts to feel like you’re actually reading rather than deciphering. Just takes a lot of time and effort to reach that point.
The decipher-as-you-go method doesn’t work for everyone. It’s worth trying at least once to see whether it works for you.
For those who do decide to read Yotsuba, there’s a former reading club with a lot of discussion on it.
There’s also current and former reading clubs for absolute beginner readers.
These are great because there’s conversation between other learners asking questions and getting answers, making it easier to learn the grammar along the way. You can also ask questions in the threads, even years after the club has ended, and get still get answers.