Work for a US company in the UK, work hard and angle for a transfer to the US office (also could be a UK company with offices in the US etc.) - look for L1 visa.
Find an American SO, get married and apply for a spousal greencard - look for CR-1. They’ll need to prove they have the resources to look after you.
Those are your two realistic options. If you were American looking to live in London you’d have a similar - perhaps slightly larger - range of options. Now you may understand why losing free movement of people to the EU 27 was such a big deal for those who want to try living abroad.
Work for a US company in the UK, work hard and angle for a transfer to the US office (also could be a UK company with offices in the US etc.) - look for L1 visa.
Find an American SO, get married and apply for a spousal greencard - look for CR-1. They’ll need to prove they have the resources to look after you.
Those are your two realistic options. If you were American looking to live in London you’d have a similar - perhaps slightly larger - range of options. Now you may understand why losing free movement of people to the EU 27 was such a big deal for those who want to try living abroad.