I'm playing DnD 5e for many years now, and I love it. I love playing it so much that I felt like I wasn't playing enough of it, so I went from playing only with my friends to playing online in public discords.
After a short period of adaptation, I got used to the limitations this brings, but there's one thing that I feel is weighing me down heavily, which is my complete lack of understanding of The Forgotten Realms lore. With my friends, we pretty much ignored this setting entirely. We used the DnD 5e mechanics on our universe we created along the way; we made our adventures from scratch and even changed racial lore (lifespans etc.). Coming up with this "homebrew" setting was a lot of fun, and I don't regret it, but now that I want to play online, most discords utilize Forgotten Realms lore. It's hard to get immersed in a world you know nothing about, especially when you're playing a wizard!
I've looked online, but the only reliable resource I've found was a youtube playlist with over 100 lore videos, which I'd love to watch eventually, though I don't have the time/energy at the moment. It starts with the very beginning (creation/deities/etc.), which means I'd probably need to get in very deep before I start learning bits for our game.
So my question is simple, what is the best way to attain the lore-knowledge foundations required to understand and appreciate the world of the forgotten realms while playing in it (and where to expand from there).