how to deploy a application in aws

Can you be more specific on what you are looking for? As far as I understand you from your questions you want to move your application from on-premise to AWS.
You can create EC2 instance and move your codes or deploy. 

the question is very vague.. what we need to know is your current implementation.. do you have a container that you want to publish (i.e. docker) or you have a web application (ex: php) that you want to host, do you want it to be serverless, or just host it on some machine online, do you want it to be scalable..

on the other hand, the easiest way to publish an application to aws, is using aws elastic beanstalk.. with a few clicks, you will upload your code and aws will do everything for you.. here's a guide: https://aws.amazon.com/getting-started/hands-on/launch-an-app/

hope this helps,
db

AWS == Any old hosting

Nothing special about AWS... except every interaction to manage instances is far more complex + time consuming + error prone than using dedicated servers... also far more expensive (read many EE threads about AWS Surprise Bills).

Once you have an instance running, you simply have a Linux or Windows system you treat like any other hosting.