Cloud Computing

Cloud computing is an internet-based computing that provides shared computer processing resources and data to computers and other devices on demand. It is a model for enabling ubiquitous, on-demand access to a shared pool of configurable computing resources (e.g., computer networks, servers, storage

You can be a cloud analyst, cloud architect, mobile application developer, cyber forensic analyst, etc.

Yes, it's a good course to pursue after class 12th.

In my opinion, Internet Of Things (IOT) is going to be the future. Actually above mentioned subjects are all related to IOT. You need to learn these technologies to get into IOT. You can also look for courses on these topics in Coursera.

Cloud computing and cyber security is more demanding stream but it's tough to make career directly in cyber security cell. Could computing and big data analysis is recommended according to me. MCA is also good in IT field as it has so many job opportunities.