If he has eaten a little bit, including his cecotropes, it seems likely that he will start eating more. Does he have a hidey house in his cage? It’s a good sign that he ate when you sat with him. It may be good if you are in the same room as him, but without fussing over him. You could perhaps read a book or listen to music?

Do you have the same pellets that he got in his former home? How old is he?

Oh good! Try to keep the house quiet and calm for the next few days while he continues setting in and I’m sure he’ll start eating even more.

Hay is the most important food, so its really great that he’s eating that!

He probably just feels insecure in his new environment. As Pinkiemarie says, try to keep his environment reasonably quiet these next few days, and he will most likely start to eat more! You can absolutely talk and play some music for him, but obviously avoid for example loud volume death metal and wild partying.

You can read aloud from a book or magazine to him, just to get him used to your voice.

If you don’t have the same pellets as the breeder, that could be why he is reluctant to eat the new pellets. Rabbits are naturally cautious of new food. They are very curious though, so if you keep serving him pellets, he will probably try them out soon, and find them delicious.

A very young rabbit is obviously more physically vulnerable than an adult rabbit, paticularly gastro-intestinal-wise. So keep an eye on his poop. Rabbit poop contains important information about the rabbit’s health.