Whenever we develop any application, we have to focus on cloud deployment to make it highly available. Microsoft provides its cloud services through Azure in two different models called IaaS (Infrastructure as a Service) and PaaS (Platform as a Service); each model has its own pros and cons.
If you opt for the IaaS model, we will have more control over the infrastructure where your application deploys. That means you can select hardware and software configurations based on your requirements. But after deployment, it’s your responsibility to maintain the application and infrastructure, and you need to allocate extra people to support the servers.
Microsoft Azure provides PaaS (Platform as a Service) model to overcome the infrastructure issues. Using PaaS services like Azure App Service, Azure Service Fabric, Azure Functions, etc., you just need to focus on your application code, and Azure will take care of infrastructure. All these PaaS services are highly available and will have fault tolerance configurations.