Excalidraw Windows Desktop Version Using Kooboo. For Mac Version, see video link below.
Download from the release or source code. Click Kooboo.exe to start, Then, click on "Start"
If prompted by a firewall for Internet access, click "YES" to continue.
On the login screen, enter the following credentials: user: admin, password: admin
Click the link below to open the Excalidraw App and log in again using the same username and password.
You are now at the Excalidraw file manager page,
Click "New" to create a new Excalidraw document.
Above works for Windows. For Mac, please see below videos to do it yourself.