A child who is 2 years and 3 months old biting or hitting is actually quite normal at this developmental stage. But it can become a habit if it’s not gently managed early on. And not necessary it takes till 3 years old.
As each child development it’s very unique.
At this age, children often struggle to express emotions like frustration, tiredness, or overstimulation and they may act out physically because they don’t yet have the words. Biting or hitting can also be a way to get attention or express excitement.
And the most important to be present and keep boundaries.
If he’s at day school, of course you can’t see everything that happens but you can support him emotionally at home like naming his emotion, saying “we don’t hit, hands are for helping, hit this pillow if you want.” If biting as well, show what he could bite, but don’t allow to bite you or others, by gently diverting. Some kids as well can bite if their gums are swollen. Then it’s more about physical discomfort and pain. For that I was giving special dry bread what melts but child can’t choke.
With consistent and calm responses, most children grow out of this naturally. Ofc noticing what child did good helps too.
I would recommend to observe the child and you’ll notice exact reason.
I always for everyone recommending before asking how to search for a root cause why. There is no deadline when each child should develop or gain one or another skill.