Can anyone tell me how to put a breakpoint on a string which exists on resource section:

Launch a process
Go the the memory map and search for string
Ser breakpoint on it

[problem] -> when I reload the app again I need to perform all the steps given above to set the breakpoint. Does anyone knows who to set a breakpoint in this case which persists after app relaunch.

Use a hardware breakpoint. You can have four of those instead of one regular memory breakpoint, they don't slow down program execution, and are also saved across debugging sessions.

That, or place a conditional breakpoint on FindResource, filtering on the requested resource ID. You can find out this ID by pressing alt-E, rightclicking on your .exe, and selecting "View resource strings".