How can I make curved path ?

I want to make curved path and physics like this ? But ı dont know this path is a script or model parts ?

 

99% It's a pre-made model. Yo could try to build a path out of prefabs (think of them like LEGOs) and instantiate them to create a procedural generated map. Alternative would be an asset that help in creating such "curves". Still tho becoming familiar with blender helps.

 

Okay, thank you, but how can ı make objects follow the road.Because Physics is will be difficult.

 

As for objects "follow" I guess you mean that you will "ride" the right way? If so - NavMesh.

 

I dont know, in this video it not looks like nav mesh ? is that so ?

 

Im not sure if it's made on Unity, but I think nav-mesh would be a good idea there. Especially when you can slide both on the flat side and the U-side.