Among Ground Pole and Half-Wave Dipole, which one has higher gain?

Any link/idea to make Ground Pole antenna and Yagi-Uda antenna suitable for FM band?

Depends on if the transmitter antenna is horizonantaly or vertically polarized. Ground Plane is a vertically polarized antenna; Dipole is horizontally polarized.
Yagi can be mounted either way; TV in the US is horizontal, FM broadcast is both; with more power in the vertical plane (for cars, which usually have vertical antennas).

Here is a good **broken link removed**. ( I cant run it because I have Java disabled due to its security vulnerability).