Welcome to Microsoft Q&A! Thanks for posting the question.
To better assistance you on this, could you please let us the following for more clarity:
Are you attempting to install the SSL certificate onto your domain on an Azure VM or any Azure resource?
What specific instructions (or Azure doc) are you referring to?
Just to highlight, Azure offers several ways to host websites/apps: Azure App Service WebApps (PAAS solution), Virtual Machines (IAAS), Service Fabric, Azure Storage (for static website) and Azure Static Web Apps. Kindly see 'Decision tree for Azure compute services', for more details on this topic.
Azure App Service enables you to build and host web apps, mobile back ends, and RESTful APIs in the programming language of choice without managing infrastructure.