There are two tv series about time travel. Timeless where they can go back and change things, but of course each small change can have a huge effect into the future. you never know how preventing one person doing one thing might change lives, prevent people being born..etc. The heroine comes back after the first trip to find her sister wasn't born, her mother is not an invalid. She was actually not changing family things but something nationally important. You were unable to go back to talk to yourself in this story line.
The other series, Frequency, was not quite time travel but a policewoman who was suddenly able to talk in CB radio to her father, also a policeman, who died when she was eleven. There are cases where the wrong person was convicted and a serial killer was never caught, so killings go on. She is able to give her father information that she can get because of improved police technology. Again this changes her present.
Would you want to go back and change something risking the things that might also change? We've just talked about it after I read this and I said a point at which I might not do something, and was reminded we'd not have had the loving and wonderful dog we found and had for nine years if we'd not gone to Spain for two years .
We got her at two days old and bottle-fed her, day and night, every two hours and she grew up thinking she was a little girl. She actually was a little girl in a dog suit. She understood so much language. She died 3 months ago and we're still mourning her, which is why I couldn't not want to have done that bit of the past.