A mic preamp will boost the level of the signal from your mic, thereby bringing it up louder when you record, without extra noise or distortion {if it's a decent one}. You can use them on any kind of mic.
Phantom power is generally used to power condenser mics and should be on a preamp and many mixers. Condensers won't work without phantom power.
Years ago, when I asked a sound engineer what phantom power was, his reply was so complex and convoluted, he may as well have been explaining the construction and development of the brain of an embryo child ! I hope mine is a little simpler.