how to play video without store in db but it store in C# app

You can use “Amit Gupta” suggestion which will open an instance of Windows Media Player and play the video file you are passing.
The main issue here is that you almost have no control over the player or the video. Also, you need to make sure that Windows Media player supports the video format and the audio format.
If you want to have more control over the player and play wide set of video file formats, you can use LEADTOOLS Multimeida toolkit. Using LEADTOOLS, you can place the player directly on your WinForm and play the desired video. The code is quite simple and looks like this:
Check this .NET tutorial:
https://www.leadtools.com/help/leadtools/v20/dh/multimedia/to/creating-a-basic-leadtools-directshow-player-application.html