I think my child might be behind socially due to limited peer interaction—how can I help?

My son ( 3 years old ) prefers playing on his own at nursery and doesn’t really interact much with the other kids. He’s happy doing his own thing and seems comfortable, but it does make me wonder if I should be concerned.

I’ve actually been aware for a while that socially he might not quite be “there” yet. Part of me wonders if that’s on us a bit—we don’t have a huge close family with lots of cousins around, and most of our friends don’t have kids the same age. So he hasn’t consistently had that peer-to-peer interaction growing up, and I’m starting to think that might be playing a role.

It was his nursery teacher who really made me aware of it more recently. She mentioned that he struggles to sit and eat with the other kids at the table. He sometimes doesn’t eat much, then gets really hungry later and ends up eating with her during her lunch time.

That part feels like something I can improve at home—maybe by having more regular sit-down meals together as a family so he gets used to that routine.

What’s interesting is that outside of nursery, he’s quite social in other ways. He comes everywhere with me (shops, park, etc.) and interacts really well with adults. He’s also fine around kids in our family, and at the park he seems okay being around other children too.

I’m trying to figure out the right balance. I want him to be as prepared as possible socially, but I don’t want to push too hard and knock his confidence either. At the same time, I don’t want him to default to only adult interaction and miss out on building friendships with kids his age.

Has anyone else been through something similar? Is this just a phase/temperament thing, or something I should be more proactive about? And what are some good ways to gently encourage social interaction without putting pressure on them?