It depends on the policy your purchased. Your London (actually UK) policy may allow cover you third party (ie legally) for use in the EEC but it is best to check this with your insurance provider - If you require more cover they will be able to add this for you.
6 to 10 hours
You will need to allow at least 3 hours for the drive because of London traffic.
Yes you can drive your car anywhere unless you have special restrictions on your insurance
Contact an agent some states allow/offer 'drivers' insurance coverage/polices.
To obtain insurance to learn to drive, you can be added as a named driver on a family member's policy or purchase a learner driver insurance policy. These options allow you to practice driving legally while being covered by insurance.
Allow three hours.
You should allow about two hours.
You have to pay because you let them drive you car so it is your fault!
It depends on our father's insurance. My children may drive my car because my insurance covers anyone I give permission to drive my car (they have have a valid license). However, my ex-wife's policy does not allow it - by not having this option she actually lowers her premium. This can vary from state to state and insurance policy to insurance policy. Have your father call his agent and get the correct answer for his policy. He may have to make an adjustment to his policy to allow you to drive his car.
Most auto insurance covers anyone you allow to drive your car, except people living in your house.
You should allow 2 hours.
If you own a car and buy insurance to cover it, you are covered although the insurance is on the car. You can allow other people to drive the car and they will then be covered even if they don't have insurance.