Floors Creaking when walking across

Some of the rooms, stairs and ground floor appear to have chipboard flooring, over time it's been ok, but now there is a lot of creeks and some parts of the floor has become weak, i.e. when walking across room floor, drawers on the other side may shake, where it should not be. It may mean that the chipboard needs to be replaced with proper floorboard or solid hardwood floors, but something needs to be done. Also landing floorboards may need changing. What the best way round this, who would be ideal trades person to look at, quote and repair?