How to make a background move/change?

First one looks like an object being moved past the window and then despawned and respawned at the beginning again. Maybe just a loop of CFrame?

Second one looks like there is a model split up into segments which are teleported and then moved past the train on repeat, similar to the first but more segments so the model can be well out of frame before its teleported

Idk, just a guess, good luck!