Some grammar points come easy to me and others, not so much. I found that reading is a huge help with solidifying things I’ve studied. If you want to practice reading, try Tadoku: they have a lot of beginner friendly graded readers and many have audio. The Level Start/Level 0 books are short and typically use easy grammar and vocab. Seeing grammar in action might help you remember grammar better.
(If you already knew about that site, sorry for the redundant recommendation!)
There are also these posts on Reddit
2021 updated Free Tadoku graded reader PDFs 1,796 total pages for reading : r/LearnJapanese
All Free Tadoku Graded Readers with Audio and Cover Images : r/LearnJapanese
I think the program is flexible depending on each user’s needs, but it may take time to develop your personal study method. I use bunpro because you can type your answers in reviews - I can’t seriously engage with apps like Anki where you just push a button for each card, I need to interact physically with the material. I use bunpro as my primary learning source for grammar (some people just use it to review). Learning here works for me because I find comparing the example sentences gives me context for the tone of each grammar point. When I struggle with grammar, I usually supplement my studying with explanations I find on YouTube, usually from Nihongo no Tabi.
I took Japanese classes in college however, so I’m not a total beginner. I can’t speak for how well the program would work for someone starting from zero.
I used to be the same way, back when I was cramming kanji and grammar faster than I should have (I was a little addicted to rushing through WaniKani). I’m making a huge assumption about your situation here, but is it possible you’re trying to go too fast? It wasn’t until I burnt out and came back again, but prioritizing understanding above speed, for BunPro to work for me. Instead of rushing through as many grammar points as possible, like I did with vocab, when I slowed down and started reading the whole Bunpro sentence (and understand it, not just be able to know the sounds without furigana) did it really start to stick.
Also, I had to take a break with learning when my life got very stressful. Even though I could have found the time to do reviews, like a sponge full of water, it was like my brain simply did not have the capacity to handle learning more information whilst I was dealing with very complex and difficult life situations. Once things slowed down again outside of my Japanese learning life and the proverbial sponge was squeezed, then I could feel my brain become receptive to learning again. Maybe you’re in a similar boat?
Or simply maybe the resources BunPro offers really just aren’t for you, and that’s okay too! I find that a multi-pronged approach is best for me, so just keep trying things and eventually you’ll find something that works for you! 頑張ってください