Yes, it is possible to rent a car at the airport without having a flight. Many car rental companies have locations at airports that are accessible to the public for car rentals.
No, it is generally not possible to skip the second leg of a flight without risking penalties or having your return flight canceled.
Geneva Airport is all in Switzerland, but it is on the border and it is possible to access the airport from France and catch a plane without officially entering Switzerland. Basel Airport is the other way around. The airport is in France, but there is a fenced off road leading from Basel city to the airport. You can then check in and board a flight without having to (legally) enter France.
For a flight to Albany you would land in Albany International Airport. Mainly used as a hub airport, but has the distinction of having Air Force One land there 4 times.
I don't think it's possible to get a regularly scheduled commercial flight from Boston to anywhere in Kansas. The nearest large airport having direct flights to Boston for most of Kansas would probably be Denver, which is about a 4 and a half hour jet flight. For eastern Kansas, Kansas City (the airport itself is in Missouri) would be closer, but it's a smaller airport with no direct flights to or from Boston. For the southeast corner of Kansas, Dallas/Ft. Worth airport might be marginally closer than Denver. Flight time would be roughly the same 4-5 hours.
No, that is not possible.
No, having a boarding pass does not automatically check you in for your flight. You still need to go through the check-in process at the airport or online before your flight.
A layover during a flight means that you have to change planes at a connecting airport before reaching your final destination.
No its not possible
Yes, it is possible to celebrate your birthday without having a party.
Checking in for a flight means confirming your reservation and getting your boarding pass. You can do it efficiently by using online check-in, arriving early at the airport, and having your travel documents ready.
Yes, it is possible to make a payment through PayPal without having an account by using the guest checkout option.
No, it is generally not possible to obtain a PhD without first having a bachelor's degree. A bachelor's degree is typically a prerequisite for admission to a PhD program.