Moving to London to join husband, what's the right visa for me?

Hi, I plan to marry my boyfriend, a citizen, born and raised in London and living there. We plan to marry in the States, then I will move to the London about 6 months later. I am having a hard time figuring out what and how to get citizenship, or at the very least be able to work when I move there.
I find the website very vague and difficult to navigate especially with my specific situation.

Any input would be appreciated.

Thanks!