The answer should depend on whether your home country has an extradition treaty with the country where you plan to travel.
North Korea
yes
no
If you mean incognito then yes
Oh, dude, you'd have to go incognito in countries where it's not safe or legal to be yourself. Places like North Korea, where they're not exactly known for their open-mindedness, or maybe some ultra-conservative countries where they're not too keen on people expressing themselves freely. Basically, anywhere that's not down with your vibe, you gotta put on a disguise and blend in like a stealthy ninja.
Because If there is no tourism there will be no other places to travel for the tourists and no one traveling and TRAVEL wouldn't exist.
In principle it is probably possible to travel to every city in the world. But it is far from practical. The cost of travel would be enormous and there are places where there is fighting and places that are hostile to whatever country you are from.
There are a number of places where you can get good travel insurance quotes. The best place would be the AAA as they tend to deal with a lot of travel and would have a lot of experience.
south west
To get to distant places faster than you would by car or train.
There are many places where one could get travel insurance if they were pregnant. The best place where one could get travel insurance would be through a travel agency.