These specifications mean:
VHF yagi antenna
This tells you the general kind of antenna it is: a Yagi intended to operate at VHF: "very high frequency".
This means that in the antenna's direction of maximum gain, it will receive 12dB more power than a theoretical circularly polarized antenna which receives power equally from all directions. It means that if the antenna is pointed directly at the satellite, and the satellite also has a circularly polarized antenna, you can add 12dB to your link budget. (If the satellite does not have a circularly polarized antenna, you can add only 9dB: there's a 3dB penalty for not having circular polarization on both ends).
switchable RHCP - LHCP
This means that the polarization of the antenna can be switched between right-handed circular and left-handed circular polarization.
VHF Low Noise Amplifier
This means the antenna contains an integrated amplifier. Amplifiers require power, so you'll want to read about how that power is supplied to make sure it's compatible with the rest of your system. It might have a separate power supply that you just plug into the wall. Or, it may have some arrangement to be powered over the feedline.
This is the noise figure of the amplifier. It is telling you that the amplifier degrades the signal to noise ratio by 0.8dB. An ideal amplifier that added no noise would have a noise factor of 0dB.
Frequency range: 144-146MHz
This is telling you the frequencies over which the antenna is designed to work well.
What will be the specs of a fixed antenna capable to receive the same signal (~145.8 MHz, cw and BPSK1200)?
Antennas do not "know" what kind of signal they are receiving. That is, they don't care what the modulation is. So there are quite a lot of antennas which could have similar capabilities. Hopefully with the explanation of the specifications above you can better understand how a different antenna might be more or less suitable to your needs.