Change in Number of steps in Gromacs Simulation

I am trying to process protein-ligand complex using the this link

But as the publication purpose, it should be processed for at least 100ns should be processed.

So, i need help to change the Gromacs simulation to run for 100 ns. As per the instructions, we can change via CPT file. But, i am not able to process it via uploaded cpt file.

Kindly let me know the workflow with the following change.
“Number of steps for the simulation”: 1000000 to 100000000

As i have tested using md.mdp file from

But, it is not working. So, i need some sample file to run at 100ns simulation.