Yes, bees are sentient – and so are slugs, fish, monkeys, dogs and people.
Being sentient comes in degrees. Generally, I accept that other people are sentient because they are likely to be somewhat similar to me; their me-like behaviour persuades me that they are sentient.
That’s the case we make for dogs. Exhibiting happiness, guilt, and hunger create a persuasive case that dogs are sentient. Monkeys, probably the same though perhaps a little less, mainly because we know less about their behaviour.
As for fish and slugs, we have so little in common with them that we tend not to think of them as sentient. It might be reasonable to say “Sentient, but not as we know it.”
Which leads to a sliding scale, and bees are on it: they are sentient, but not as we know it.
https://mellifera.blogspot.com/2023/06/bees-sentient-but-not-as-we-know-it.html