Give me break = This is a way of expressing that you disagree with something or think it is a stupid idea.
A 'fleet' is a group of ships, but also used for cars; a company with have a fleet of cars for its managers to drive. A 'taxo fleet' would have this meaning- it could be all the taxis in a town, or it could be those owned by a taxi firm.
If you made friends thought the internet, it suggests that you met them on the net and went on the meet them in the real world, while a friendship over the net is one where you only contact on the internet.

I see nothing wrong with 'net friends'. 'Penpals' is still used, but it doesn't have the same idea to me.