If they had boats, they would almost certainly have been of one of three types.

Type 1, raft. Generally rafts are cumbersome and difficult to use against prevailing currents and winds. They almost certainly would not have been using sails.

Type 2, dugout vessels, either single or multiple hulls, lashed together. Again, no sails. Much easier to paddle. Note the Polynesian voyages for equivalent distances. The Basque peoples have been noted voyages for a very long time.

Type 3, skin boats, either curraghs or bull boats. Relatively easy to construct, capable of voyaging. Within the capabilities of Neolithic humans. Used in Asia, Europe and North America. Prototypes for canoes and similar boats. Note the Brendan voyage for a long voyage in this type of vessel. They are still in use in various parts of the world.

Yes, such a voyage is possible.