Here's the fix, I found-

Open Steam App and Go to Library.
Select the "Black Mesa" game from the list.
Right click the game's title "Black Mesa" and Select Properties.
Go to the"General" tab and find the "Launch Options" section.
Enter "-force_vendor_id 0x10DE -force_device_id 0x1180 -dxlevel 95" and Close the properties.
Launch the "Black Mesa" game.
After closing the game, remove "-dxlevel 95" or the settings will reset each time the game is launched.

Good Luck hope this help my fellow Arc enjoyers