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Hello! I am new in CircuitLab. I would like to now ho to obtain the graph V_DS - I_DS (Drain Source Voltage - Drain Source Current) as the result of a circuit's simulation.

Thank you!

You are describing a "curve tracer".

It normally plots Drain Source Current vs. Drain Source Voltage at a given Gate Source voltage (Vgs) (or a range of Vds values).

You can do the same thing for Ic vs. Vce at a range of Ib values for a bipolar transistor:

It works by doing a DC Sweep of Vce and plotting Ic. It runs this simulation at several different values of Ib and then plots all the traces overlaid.

To find out how to do this, start by reading the Documentation about DC Sweep analysis:

https://www.circuitlab.com/docs/the-basics/#dc_sweep_simulation

Then read about how to plot outputs:

https://www.circuitlab.com/docs/the-basics/#plotting_outputs

These examples might help you understand how to sweep parameters so that you get several DC Sweeps each a different parameter values (in the case of the bjt curve tracer this 2nd parameter is the base current):

Then look carefully at how the bjt curve tracer is set up so that you undertsand how it works using these various features of CL.

Then make a similar circuit but using a FET and remembering to drive the gate with a voltage source instead of a current source.

:)