But, Chandan: You already asked the same question here:
It is a violation of Community Guidelines to create duplicate threads or posts.
[I'll flag this thread for deletion]
re: "will my profile be locked private again?"
But so what?
Whether or not your profile is set to private has nothing to do with whether or not you can do your work for current clients, or submit job proposals to any posted jobs.
It just means that you aren't showing up in searches.
And if you don't like that, you can request to have your profile made public whenever you want to.
This feature HELPS you. Because mostly it affects freelances who aren't even using Upwork any more. By making their profiles private, it makes your profile stand out more and be more likely to be found.
re: "how to know that if someone has visited my profile After sending i have sent the proposal or not?"
The Upwork user interface does not provide any way for you to know that.
Your "My Stats" page does indeed have some numbers showing how many times your profile was discovered, or viewed for the first time... But:
a) we don't know for sure what those numbers mean
b) these numbers don't necessarily mean a client visited your profile after you sent him a proposal