No, as a learner or provisional license holder you cannot drive on the motorway. The restrictions we found for a person with L plates stated the following:

As a provisional licence holder you are restricted to a maximum speed limit of 45 mph and you must display L-plates on the front and rear of your vehicle. You must have a qualified driver with you who is at least 21 years of age and who has held a full licence in that category for at least three years. You are also not allowed to drive on a motorway.

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