Both are good to visit.
The UK has plenty of history spanning back to the beginning of civilisation. It also has 4 cultures - English, Scottish, Welsh and Irish. There are a few monuments and historic buildings. There is also plenty of entertainment.
The US also has some history, particularly Native American history. There is plenty of entertainment and plenty of night-life in some cities.
A passport.
Depends on your opinion.
No need for a visa, as the UK is a participant in the Visa Waiver Program.
its not that dangerous to visit the UK
It isn't
Yes you can, as long as your passport is valid
yes
The United States is freer than the United Kingdom because it is economically better than the UK.
Depends what your 'visit' is for really........if it is for work or education then yes you would need a visa. If your visit is purely as a tourist then no, you would qualify under the 'Visa Waiver' program and would be able to visit the UK for up to 6 months without a Visa
No, you cannot visit the USA with a UK student visa.
Yes, UK citizens can travel to the US with a valid passport and may also need to obtain a visa or an ESTA (Electronic System for Travel Authorization) depending on the purpose of their visit.
He came to seek a better life