When you highlight some text in a text frame and start typing, the first keypress does not respond and the first character is skipped. This issue occurs only on Windows system.
Before you perform the steps below, make sure that you have InDesign 13.1 installed on your system. You can check the version of InDesign installed on your system by going to Help > About InDesign.
You can update InDesign CC on your system from the Creative Cloud desktop app. For more information, see Update Creative Cloud apps.