Whichever one best suits your needs.
45
It depends on your needs. In general, you should buy a handgun that fits your hand properly. Beyond that, buy a gun that meets whatever other requirements you have.
Two hands.
NO!! Although the bullet diameter is the same, the case length is different and should not chamber in the 380 caliber handgun.
It should be marked as to caliber on the barrel.
I say your head and chest
Florida does not require handgun registration, so the answer is, you don't. If you are referring to a permit to carry, check with a local gun range. They should be able to tell you how to go about it.
If you have a handgun carry permit, definitely. The handgun carry permit covers "any handgun that you legally own or posses."
Shooting glasses and hearing protection are the most important.
why can you get a shootgun at 18 but not a handgun
A regular handgun, no. There is no registration in TN.
The biggest reason is that it is illegal (in most of the U.S. anyway)