I'm not particularly tech-savvy, forgive me, but I'll do the best I can.
So I had just created a new world, I punched down some wood, and proceeded into a hole in the ground that led to a cave. I found some coal, used it to make some torches, and when I held the torches (selected the torches on the hotbar), all the block textures of every block loaded in the game flickered rapidly, from visible to invisible, and all my items in the hotbar became invisible, except for the numbers showing the quantity of the item. Deselecting the torches caused all the block textures to remain invisible, and reselecting the torches caused the flickering again. It seems that the only way to fix it is to go into the Resource Packs menu, and click done, though the whole issue begins whenever I held a torch, which is, well, kind of imperative to do during the game.