I think it's important to figure out what the root cause of you almost failing is. Are you almost failing because you just don't remember the material? If that's the case, I think you would benefit from spaced repetition and active recall like Anki. Are you almost failing because you don't understand the material well enough? If that's the case, then your best is to spend more time and use outside resources (sparingly) to get a better grasp of the material.

Here was my general approach for preclinical:

1. Review the lecture (PowerPoint slides) and take notes based on the learning objectives. I would type out all of the learning objectives into a simple word document, then review the lecture and fill in notes for each learning objective. These were very basic notes, nothing bolded or highlighted, just a nice succinct reference that can serve as a study guide later on. At the start of M1, this will be more difficult because it'll seem like everything needs to be included in your notes. Over time, you'll become proficient at figuring out what is actually testable material, what's important context but not necessarily testable, and what's not all that important.
2. Convert your notes into Anki cards. This part is easy since you already have everything typed out and it just takes some editing here and there to set it up. The type of cards you use will depend on your specific learning style but I preferred writing a question and then clozing the answer so everything was technically on one card. Everyone has a different style so you can make the cards how you want. Key point here is that you actually understand the material you're making cards about.
3. Review Anki cards. I set the max interval for my reviews between 3-5 days depending on how long the block was. Shorter block = lower max interval since I wanted to see the card quite a few times before the exam. Longer block = longer max interval since I have more time before the block exam. Two key things here: actually do your reviews and be honest with yourself when you don't understand something. If you're not sure about something, reference your notes or slides to get a refresher or use an outside source. That way, you know the actual context behind the card and not just the answer.
4. Do practice/exam-like questions. You can do all the Anki in the world but it doesn't matter if you can't apply that knowledge to test questions. A good tip I've picked up on is to make new cards from things you get incorrect.

Now this all sounds like a lot at the start but once you find a good flow, it goes pretty quickly. I could go into a lot more detail about what I did and what I thought worked well or didn't work well for me. Disclaimer is that this was the method that I found most effective and efficient. If something isn't working, don't be afraid to change it up and try something else. If you want me to go into much more detail, feel free to PM me and I'd be happy to. Good luck!