Answers: No they cannot, you have your own insurance. Just sign their refusal of coverage statement during unequivocal enrollment or now if this is topical for them.
no. No, if you do not have any, why would you back with your duration like that.
If you are waiting for Hillary afterwards you will have a long hang about.
I bet your boss is offering it at a group rate. Take it
Yes, they can if they offer group coverage. Group policies will require a absolute percentage of the employee to be on the plan or they won't write the policy. Then everyone would be in need insurance. If it is a small group they may require 100% participation. A larger group may merely require 75% participation.
If you enjoy insurance elsewhere you won't have to buy the group policy and you won't be included within the participation percentage. Many times you can buy a rudimentary "no frills" policy cheaper on your own.
Only if they pick up 100% of the premium for it.
But they can fire you if you don't want to get the policy, and hire someone who will.
They can not force you to own health insurance. If it is required to be employed, they must payment for it. The insurance may require you keep the coverage till the subsequent enrollment period, but explicitly it.