This link (http://www.mdtutorials.com/gmx/) has useful tutorials for GROMACS. I suggest you "Lysozyme in water" tutorial which helps you in simulation of proteins with GROMACS.
Actually I want to study the transition of an enzyme from open to close state in the presence of a substrate, and for this, I am planning to do targeted MD simulation which would drive the open state of an enzyme to its closed state with a particular spring constant. Therefore, I want to know if there is any tutorial for this particular simulation using PLUMED or ProDy.