When is a static route configuration useful?

When would you, as a network administrator, need to make use of the static routes setting?

In C/C++ network programming; create a simple web proxy that handles the connection between a client and server. I currently have been working on a client and server echoing each other from the geeks for geeks example but can't find much information in CODING up a web based proxy. I do understand the type of proxy to create but do not understand how to code one up in terms of client-proxy-server connection through https. The answer that I am looking for is how to create the web proxy in C. You can use the geeks for geeks example (client/server) or use one of your own.

THREAD -"C LANGUAGE" ONLY   Write a program that uses 5 threads. Initialize a shared variable with a value of 0. Each thread must add its Thread ID (tid) to the shared variable. Once a thread has done the addition, print the ID of the thread. It is important to make use of mutexes so that only one thread is incrementing the shared variable at a time. Output the value of the shared variable once all threads have finished incrementing it.