I need to synchronize two tables sql server using c#

I hope the synchronization is one way and two way.

In any case, there is no way your C# application will know any activity taken place in sql server table.

As such, you must first confirm if there is any latency (delay) is acceptable or not. If acceptable, how much, in terms of 2mins, 5mins, etc.

You can then write a C# application to do the sync and schedule that application to execute in task scheduler at the acceptable delay.

If you have a primary key on the table, may be you can check modified_date to see when table was last modified.