How can we use same thread object multiple times

why the need for a thread,what your trying todo, you can do as below

public void MethodName)
{
    // Start the task executing:
    Task.Factory.StartNew(() => OtherMethod()); // Pass parameter if required
   
    //other code goes here as you require

    // Start the task executing:
    Task.Factory.StartNew(() => OtherMethod()); // Pass parameter if required

    //other code goes here as you require
    
    // Start the task executing:
    Task.Factory.StartNew(() => OtherMethod()); // Pass parameter if required
    
}
static string OtherMethod()
{
    // 
}

You cannot run a thread more than once. If you want to reuse threads, then use the ThreadPool. A thread pool is a pool of worker threads which are always running. Those threads then normally take tasks from a list, execute them, then try to take the next task. If there's no task, the thread will wait. It will automatically handle your "work" and pushing it into a free thread, scheduling, and queuing tasks that can't be run because you're using all of the available threads.

not every time call in a sequence some other function call in between I gave just an example.

all 4 methods call different time and different sequence

Why don't you use Task.Run() and use a loop in there to run the thing you want 4 times?
It's not really necessary to create threads yourself..you know. This will run it in a thread pool

We want to call start method 4 times but we do not wan to create thread for each time.
Is it possible to create one object of thread and call same method 4 times.

Thread thr1 = new Thread(obj.value);
thr1.Start();
// doing some operaton
Thread thr2 = new Thread(obj.value);
thr2.Start();
// doing some operaton
Thread thr3 = new Thread(obj.value);
 thr3.Start();
// doing some operaton
Thread thr4 = new Thread(obj.value);
 thr4.Start();
// doing some operaton  

but we do not want to inialize every time

we'll need more details is it not async?
why not create a thread