It’s dialog between Monica and Rachel in Friends S01E01. Monica: Rach, wait, I can cancel Rachel: Please, no, go, that'd be fine! (Rachel was in trouble and came here. Monica would have a date with Paul tonight, and Paul was buzzing at door.) We know that’d is the short form of that would or that had, it is that would here. And would is a modal verb used to say what someone intended to do or expected to happen or used when talking about the result of a possible or imagined situation or event, or describing one (From Longman Dictionary). I don’t know what Rachel was trying to say. And fine here is satisfactory or acceptable? Dose it mean Okay? By the way, I think ‘that’ means going out on a date. Please correct my understanding if it’s wrong, thank you! There should be many grammar mistakes in my words, for I don’t know much about grammar. I’d appreciate it if you would tell me all about it. Thank you!