Is this grammatically correct? What does it mean and can it be rephrased? “It’s cool. I’ve learnt to live with it” “It’s cool. I’ve learned to live with it”

Yes, both sentences are grammatically correct. The difference between "learnt" and "learned" primarily lies in regional usage; "learnt" is mainly used in British English, while "learned" is more common in American English. Meaning: The speaker is expressing that they feel okay about a situation or condition (indicated by "It's cool") and that they have accepted it or adapted to it over time ("I’ve learnt/learned to live with it"). Rephrased: - "It's fine. I've gotten used to it." - "It's okay. I've adjusted to it." - "I'm okay with it now. I've come to terms with it."