You can, but there are at least three reasons why you will probably prefer automatic delivery for such an important home comfort task:
If your tank gauge is faulty, you could get a false reading. (A new gauge costs about $50, and should be replaced if it can no longer provide an accurate reading.)
If you have an older underground tank, you’ll have to keep “sticking” the tank (inserting a long stick into it) to get a reading. Not fun during a February blizzard!
A sudden cold snap will cause you to use more fuel than you’ll realize. Before you know it, you could have an empty tank and a very, very cold home.