@Groundwork2022 Oh I meant OP can, if he used Google Docs, prove that he wrote the essay himself by showing the edit history - shows major changes and provides date/time and which additions/edits were made.
But yes, regardless, he did most likely share his paper to this “friend”. If he can prove that, he should probably be able to show he was the one who shared it.
A lesson nonetheless, but seems feasible to prove really if OP shared it.