The good news is time paradoxes are impossible, you always are in your own universe and there’s no such thing as the past and future as “places” you can travel to. You see dinosaurs? Go ahead and saddle up, you can’t possibly break anything.

Current scientific theories that propose time travel is even remotely possible describe the system as more of a wormhole connecting two points in time/space. One entrance would be moving at relativistic velocity relative to the other opening, or orbiting a black hole or other super dense object, this would create a small delay between one opening and the other that would grow longer and longer over time, meaning in theory you could go back through the wormhole and come out at a point further back in time.

The catch is you couldn’t travel back in time further than when the wormhole was constructed.

Setting aside the fact that it may be impossible to make wormholes entirely, the other catch is this is probably as impossible as moving faster than light, meaning it’s kind of “nonsense” to talk about. Time as we know it is just evolution of entropy, motion of particles and their relative states. If you found a way to “wind back” this evolutionary motion, you wouldn’t be traveling in time as much as reconstructing some idea stored in your own memory. Meaning, no altering the past to affect the future.

The best you can hope for is making some kind of gateway to some other universe that’s almost identical but just out of synch with our own time-frame so it appears to exist in a prior state. Assuming multiple universes even exist. This may also be a deeply “human” idea that we just invented because we have geographic brains that think of time and space as physical things.