It is a low frequency RF "tuned" amplifier--that is, narrow bandwidth gain. This is typical of the type of amplifier Hams used to use 20 years ago.
C22 is just a capacitor to ground.
C21 resonates with the inductor to form a "parallel resonant" tank circuit. At resonance, the capacitance cancels the inductance, and there is an RF high impedance between the collector and the power supply.
The inductor is a 3 turn inductor. You would need to know its actual dimensions to figure out the intended inductance. If it is a surface mount coil, just go to coil craft and look up a 3 turn coil for a guess.