How to calculate the position on the map?

Question

Google Maps

The task is as follows:
On the maps, let them be Google.
There are:
1. Point A and point B
2. Route between points
3. Distance between points
4. Start time of point C from point A
Required:
1. At any time, know where point C is on the route
2. Kick in the right direction , to understand how to make it so that if there is another parallel route X Y with point Z, then how could the distance between C and Z
be calculated? 2 point must be calculated on the backend

Answer 1

Have you looked at OSRM ?

Answer 2

You didn't say anything about the speed of point C. Without knowing the pattern of movement, it is not clear how to calculate the position of the point.
As for distance, use the haversine formula to determine the distance by coordinates if the points are not far from each other: