IaaS is a cloud service provider that manages the entire infrastructure, including its server, network, virtualization, and data storage, with the help of an Internet connection. You can access it with the API or dashboard or can rent the infrastructure. You can also manage things like operating systems, apps, and middleware, and the cloud infrastructure takes care of hardware, networking, hard drives, data storage, and servers. It also takes care of outages, repairs, and hardware issues.
Examples of IaaS are Azure or AWS.