As a M1, I think it is fair to maybe relax on trying to jump into the whole boards prep game. When I was a M1, it felt premature since my mentality was I need to first learn how to learn. So for the first semester, I did not use any board prep materials at all. Not FA, Pathoma, B&B, nothing. When I started the spring semester, I told myself, Well, now that I know how to study, let me see where I can experiment, and by that I mean where I can incorporate boards prep. So, another thing to keep in mind is that there is a lot of stuff in first year that may not be terribly relevant for Step 1 -- Step 1 has tons of pathology which you should get your second year, so not finding a B&B correlate is not unusual.
But, to give you specific breakdown, I'll tell you what happened during my second year: my PBL group would agree on all the readings ahead of time, before the cases even were known (we had a vague indication). I opened First Aid and Pathoma, and we reverse engineered it -- we made sure to pick readings and chapters from textbooks that were in FA. If a chapter, in say, the physiology book was 20 pgs, but only 5 pgs covered something in FA, then that would not necessarily be our priority. I was okay with studying some material on my own via B&B, Pathoma, and Sketchy. In fact, I learned Biochemistry and Endocrinology basically all through B&B. I didn't need to see everything in PBL. So, when you say not all of B&B covers chapters I assigned or get assigned, it should be the opposite -- assign chapters that are in those resources. Now again, you are a first year I presume and I had the exact same sentiment about missing out on questions and doing poorly on an exam and possibly even failing. I probably glossed over this in my initial post, but after I took the last exam of my first semester, I genuinely was unsure if I had passed the exam or not, and worried I had failed it and thus would have to remediate the first semester. I got a high B for the course (the course only has 3 exams in total, so they are stressful). Why am I saying all this? It is okay to focus on the chapters right now if you want to. Find as much of the correlates in Anki as you can, but not every thing needs to be in those premade decks (although everything in those decks, specifically Lightyear, are all highyield).
So, I suggest not worrying about finding supplemental videos for everything in your chapters at this point in time. Find them where you can, but if you get assigned a chapter on something not too relevant to boards, just take it in stride at this point. Next semester, you can start pushing off the low yield content -- as long as you are confident you can still get good marks on your exams! When I completely abandoned my school's curriculum during the fall semester of my M2 year, I ended up scored in the top 20% easily. The exams covered ore highyield material, but even the low yield material on there I was able to answer with some degree of confidence only because I know the highyield material so well (eg. if a question asked about a MOA of a drug, I could r/o 2/4 options since I knew what they were for, left with 2 options and I was okay with those odds). So at my peak of using Anki, it was as follows: go to a PBL session, talk about case, agree on reading objectives (while making sure they were in FA/other board prep resource), compromise a little if someone wanted a chapter or reading on something clearly not relevant (can't win all battles), go to the library, begin watching the B&B videos, unsuspend the cards in Lightyear, and rinse and repeat. Closer to exam date, I would do practice questions from some resource, like the Robbins textbook (in hindsight, I should have utilized Rx or another Q-bank). This was my method -- nothing groundbreaking perhaps -- for M2. M1, is different, give yourself a break if you need to still figure out where you are withing taking medical school exams. I did at least. I made up for my lag by starting my board prep in the summer following first year by watching all of Sketchy, starting the Lightyear deck (it was just released at that time), and coming up with a game plan for boards basically a year in advance. You'll be fine. Take it slow, and make sure you can pass and do well on your exams this semester.
Good Luck!
