How to get the response using non-linear MIMO state space

Hello,

I am working on a project and I try to run a simulation for step response and sinusoide response. I have obtained the state-space matrices and I am required to find the responses.

I have two inputs, one non-linear which is a feedback in my system and another input which is other step or sinusoidal. I am not sure how to write the code. Can someone help me or provide sources please.

Thank you