Garage Converstion

I am looking to convert an existing integrated garage into an office space. Is this something that you would be able to assist with in terms of plans and building regulations? I'm not looking at anything too fancy other that bricking up the garage door with a window and then applying plasterboard to the walls. No reconfiguration of the current internal layout, however I am aware certain building regulation will require a certain specification.

I have attached some plans we had drafted of the house. The garage in the ground floor plan is the room we are looking to convert.