What fairy tail episode does it show natsu make a grave for lisanna?

There is no episode of Fairy Tail where Natsu makes a grave for Lisanna.

Lisanna's "death" was a misunderstanding. She was actually taken to Edolas, a parallel world, by Mystogan. She eventually returned to Earthland in Fairy Tail episode 101, "The Return of the Fairy Tail!"

Natsu, along with the rest of Fairy Tail, was heartbroken at the news of her supposed death, but they never buried her.

Let me know if you have any other Fairy Tail questions!