App signing in Azure for WDAC and Microsoft Intune nightmare...!

Can anybody help with this sanity check? I know nothing about Azure and need to sign an app for deployment under WDAC and Microsoft Intune. I've spent hours on this and its getting frustrating!

So to summerize, I wrote a desktop app in VS 2022 for a customer a couple of years ago and provided them with an setup.exe and .application file to install it. The app is working fine but now they have come back and asked me to digitally sign it so that it can be deployed under WDAC and Microsoft Intune. Not having any prior knowledge of that I enlisted the help of Copilot AI assistant and have been trying to follow its instructions to get into a position to sign the app. I've been using Azure and set up identities and other element within but I always come up against some roadblock I can't get past like for example, Copilot asking me to add a 'role assignment' which is not showing as available. The whole process just seems very complex and impossible to understand. But that could be Copilot sending me down the wrong path.

I will persevere with it but I just wanted to ask, if anybody knows, am I going down the right path here? Is Azure the only or best way to do this or is there an easier way?
I'd love to hear from anyone who has experience with this.

Thanks in advance