How does time work?

Hello Miki, in the video https://youtu.be/wwSzpaTHyS8?si=N4VApMt8ZodNlQVW it is said that according to the theory of relativity, time is an illusion, similar to what Kant said.
a) Do you think it is true that time is indeed an illusion?
b) And if not, what form of time do you think is correct (like Bergson, for example)?