During summers in college, I had the opportunity to work for the National Seashore. Part of the job at Race Point was to inspect the vehicles before they went onto Race Point. This introduced me to "the culture" that these drive-on people had. They packed the 4x4 with people and the essentials for a day on the beach. Once they had the seats on the sand, they didn't leave until the sun went down. Some even stayed longer and lit a fire. In my opinion, this is how you beach. Laid back, uninterrupted and secluded. They brought what you needed and if you didn't have it, they didn't need it. It is a row of cars and everyone has the same mindset.
While living in Boston I got the Duxbury Beach Oversands Pass every year for an easy escape from the city. My first date with my wife started at Granite Links driving range and ended on Duxbury Beach ( shout out Wolaver's Wildflower Wheat )
Now living back on the Cape we have the Sandy Neck Pass for afternoons that we want to escape. My cell phone and email work there!
If you have never been out, visit the town websites for information on what you need. Deflate your tires and enjoy.
Here is a list of all the drive-on beaches on the Cape.
( Cape Cod Time article 2020 )
Sandy Neck Beach, Barnstable
One of the most revered and certainly one of the most popular beaches on Cape Cod, Sandy Neck is a six-mile long barrier beach. This beach is known for its off-roading trails, though often falling prey to plover-related closures, buying a sticker here is a risk worth taking. Sure, the water’s cold. Yes, the shore is rocky. But these are the sacrifices that we make for days of bringing a grill and a cooler full of 100% non-alcoholic beverages (hey, rules are rules). You can go for the day, set up a fire in the evening, crash in your Winnebago all night long and wake up early and watch the sunrise up over the Bay. Not a bad way to spend a day on Cape Cod. 
Head of the Meadow Beach, Truro
The off road vehicle corridor at the Cape Cod National Seashore is comprised of miles of unspoiled beaches managed by the National Park Service to accommodate ORV enthusiasts and other beachgoers. While they can be tricky to deal with in terms of beach fires, the Seashore is accommodating of fishing and pets. While often shut down for those plovers, there are few things more beautiful than the miles of unspoiled natural scenery at the Cape Cod National Seashore.
Chapin Beach, Dennis
The Town of Dennis is blessed with beautiful, long, clean, and sandy beaches on the north side, notably at Chapin Beach and Crowes Pasture. The Dennis Conservation Commission allows the area to be traversed by beach vehicles if used cautiously, with due concern to environmental and human values.
Race Point Beach, Provincetown
Take all the nice things I said about the National Seashore vis–à–vis Head of the Meadow and apply them here as well. Stop by the Province Lands Visitor Center located on Race Point Road just before the beach parking lot for some educational fun before you head out. You’re also just a brief jaunt from the Pilgrim Monument and Provincetown center. It’s a great place for surfing and bodyboarding in some of the biggest waves along the Cape.
Nauset Beach, Orleans
Beautiful sunrises, excellent bass and blue fishing, surfing, sunbathing, swimming in cool ocean waters, and year-round off-road vehicle access. If heaven was a place on Earth, it would (naturally) be on Cape Cod and it would be called Nauset Beach. Those folks in Orleans are serious about their rules: no animals without leashes, no alcohol, no fires, etc. And plovers do seem to be drawn to the place like a moth to flame. But nevertheless, the views are spectacular, the waters are rough and exciting and you can camp on the beach with your motorhome.
