my tips: familiarize yourself with the 808x instructions first, wether that be using 16-bit real mode or a DOSBox-like environment. From there, try making a small game for DOS before jumping to trying to write 16-bit instructions to bare-metal
(I recommend trying to make something with a game loop instead of something linear in order to get used to memory management)ent)
Once you've successfully created your simple game, try jumping to bare-metal instructions, try to print some text via BIOS, ect. If your goal is to build an Kernel (or OS, if you have tons of self-discipline!), read up on file systems and attempt to implement one. Create a bootloader that can exit real mode and load the rest of your Kernel!
SMART!!!
would be cool to see a shit ton of cursors hanging out chatting