I am attaching the simulation file of one of my circuit.It consists of many opamps and BJT's. I don't know how to check the stability of this circuit(I know it for single opamp circuits).

My input is V3(I_PT100_SET) and output is I_PT100_ACT .
I can see some ringing initially at output .

Can you please help me to check the stability and to compensate it.

 

I don't have the models to run your sim.

To check the stability of the total you run a Bode plot (AC analysis) from input to output, and look for peaking and phase-shifts of 180 degrees in the amplitude and phase plots.

Nest you generate a small voltage step function at the input (keeping the circuit in its linear range) to look for significant overshoot or ringing in the output step.

 

One way to check is to feed in a sharp square wave and look for ringing as the amplitude is varied. That should work in simulation, if it is not stable in sim, an actual circuit may have problems.