In this common source stage, the inductor acts as a current source and capacitor act as a voltage source. What happens if the inductor and capacitor are replaced by current and voltage sources respectively? How will it affect the circuit performance?
In this common source stage, the inductor acts as a current source and capacitor act as a voltage source Nonsense !
The inductor is a low impedance for DC, meaning it allows a DC biasing current to flow while keeping the drain of the MOSFET at a DC level equal to VDD.
The capacitor does the opposite, it blocks DC current and only allows AC signal to go to the load.
This circuit is a class E amplifier circuit where L1 and C1 form a resonant tank at the desired frequency of amplification. It has a limited bandwidth and is thus only used in RF amplifiers which are only used in a certain narrow band.
If you replace the components it becomes a different circuit and behaviour will be different. Listing all possibilities of if you replace this then that happens is pretty useless. Show the circuit you're interested in and then analyse it yourself first.
Your description of the circuit operation is incorrect. The inductor isolates the supply from the switching transients of the transistor. The capacitor provides AC coupling to the load resistor.
