Dumbbells might get you a certain distance with Bench and Press. But your essentially going to get nowhere in the Squat and Dead lift. Unless you have dumbbells that go up to 100 kilos each. IMO, a dumbell deadlift is also unsafe and just unnecessary.
In my routine, the only thing I use dumbbells for are 1 arm bent over row. My GF uses them sometimes for goblet squats.
If you CANNOT get to a gym. Start doing some harder body weight variations. Things like convict conditioning. Check out Al Kavadlo – We're Working Out! | We're Working Out! for ideas. Otherwise, you could do some light Rowing, squatting, pressing and benching. But it wont get you far.