Chosen Solution
My camera canon powershotsx420 hs had not showing image and full black screen and what do you think what porblem of this can i solv this or not…
Bird world sounds like either something mechanical (shutter etc.) stuck or the sensor is not longer functioning. Your camera has a fixed lens and is of course integrated into the body. Repair will be extremely difficult since parts and diagrams are almost impossible to get. I would replace the lens. Use the guides on here Canon PowerShot SX Series Repair since the PowerShot series essentially uses the same broad concept for the disassembly.