Leg press, deadlifts, RDLs, lunges, leg extensions, leg curls, hack squats, split squats. All those will hit your legs, plus there variations. Do some sprints, run hills, stairs, those will hit your legs. Im sure there are more lifts I can't think of this second as well.
While natural gas occurs in nature as a mixture of methane and other gases, propane is actually a byproduct of both petroleum refining and natural gas processing.
Natural gas and propane are both gas fuels widely used in cooking and heating. In most of the world, natural gas is distributed through a centralized pipeline network (local, national and even international), while propane is almost always sold in tanks of various sizes.