Hi @Kajal.Thakur,
Jason is right, MoorDyn does not have linearized mass, stiffness, or damping matrices because it is a time domain dynamics model. OpenFAST does have a quasi-static mooring model, MAP++, that should be able to give you these. Additionally there are external tools like MoorPy that can also provide mooring stiffness information. For a discussion of MAP++: Mooring stiffness matrix - #7 by Jason.Jonkman