OSDev.org

So, I've wanted to learn programming for quite a while, I'm also the type of person that enjoys jumping straight to the deep end. I read the introduction page that stated it was a bad idea, I still want to give it a shot simply for educational value.

I'm prepared for many hours spent troubleshooting and so on, but my end goal will be to write a custom OS for my Thinkpad T480, which I have plans of modifying quite a bit.
I don't know programming, but I have an ok understanding of computers in general(I think), though I know there's a lot I don't know and would like to know.

Also I'm not used to posting on forums or anything so if I've missed anything important please let me know

I think it’s a mistake, but have fun. But, please, don’t follow the lead of others by posting loads of questions about basic programming.

I would recommend you to try at least a small amount of programming, before attempting to write something on hardware level. Then I would recommend https://mikeos.sourceforge.net/write-your-own-os.html as pretty good start to gain some first knowledge about low-level programming.