Is there any similarity between MOSFET and BJT terminals? Are they interchangeable? If so, under what conditions?
Well, they relate quite straightforwardly, in theory: Base becomes Gate, Collector become Drain, Emitter become Source.
However they work in a substantially different way: a BJT controls the current between collector and emitter more-or-less proportionally to the current from base and emitter. A MOSFET instead controls the current between drain and source (similar working here) with the voltage between gate and source (totally different thing). A BJT takes a current and gives a current, a MOSFET takes a voltage and gives a current.
They are not really easily interchangable and the polarization areas have different effects (also the parasitics are wildly different).
That said, most (if not all) the circuit topologies have their equivalent: the linear amplifier topologies and the simple switch are the same and 'only' need a recomputed bias. In fact the simple low side load switch usually only need the base/gate resistors to be changed.
Post the circuit and we could elaborate on that.