What is the difference between it and that and i don't have and an and example ?Feel free to just provide example sentences.

whan about an object it is something close to you and that is something further away. ex. if you are wearing a shirt you would say it is comfortable, but if if you see a shirt you would say that looks comfortable.

when talking about an action "that" works better, but if you are talikg about an event "it" works better. ex. "I went to the park yesterday. It was fun," (the park was fun) "that was fun" {going to the park was fun (while on this sentence it is implied that the park was fun it means that the action of going to the park was fun)}

another example "I read a book this morning, it was intersting" (the book was interesting) that was interesting (the action of reading was interesting)