I have a 24'x24' cottage with vaulted ceilings all the way to the truss studs. Typically if I had an attic space I would need to vent the roof with a ridge vent and soffits at the roof ends. With this vaulted ceiling would I still need to drill holes in my soffits for vents and have a ridge vent?

A ridge vent does nothing unless it can pull air form somewhere els lower in the roof system So yes would be the answer.

None of this will do any good unless there is a min of 2" air space open from soffit to peak.

Use rafter vent baffles to ensure air space from soffit to ridge.

Chuck