The following includes two sections: Package installation and then adding WorknetGPT to the Salesforce Case UI.

Package installation

Worknet app is approved by Salesforce and is available in the Salesforce AppExchange. Here is a link to the listing. 

Installation required Salesforce Admin permissions and it is using the standard Salesforce package installation.

Click on the [Get it Now] button. You'll be asked to Log in. Use your Salesforce credentials. 

It take several seconds and you'll get this screen. Use [Install in Production] or [Install in a Sandbox] based on your needs. 

You'll get this screen that requires you to confirm installation details.

This screen will show when you upgrade from a previous version and similar screen for first time installation. Choose the scope that you need and click Install or Upgrade accordingly. 

You can click View Components and you'll get this view

When done you'll get a success view for the installation or upgrade.

This step completes the package installation.

Enabling WorknetGPT in a Salesforce case UI

The WorknetGPT package installs a UI control called worknetAI. You can drag this control anywhere is a Salesforce lightning UI.

For adding it to a Salesforce case UI

Navigate to the Salesforce Case UI

Edit page

Add a WorknetGPT custom tab at the right pane

Drag the worknetAI custom Lightning component to the right place on the screen. 

Save and activate.

Each use will have to login using their G-Suite, Office 365 or Salesforce SSO to get access