After you install the KWizCom Modern Apps On Prem in your site, you need to install the required apps in your site to make them available to users.
1. Click the site's gear icon and select "KWizCom Apps Settings":

2. In the KWizCom Apps settings page, install all features by clicking the "Install all" button:

You can also install only selected features by clicking the toggle button
available next to each feature.
After you install all/selected features you will see the installed ones showing active (and not grayed):

After the selected features have been made available in the site, you can activate the KWizCom apps in the relevant lists and libraries and then start using them.