If you want SSL on your EC2, you will have to use the application which is running on EC2 to obtain and install a certificate. For instance, apache or Nginx. You don't need to do extra work. You cannot use the free certificates which you got from Amazon Certificate Manager, you cannot export them for use. You can only use them on ELB and CloudFront.
You can grow your knowledge about AWS Elastic Beanstalk and many more AWS skills on Intellipaat's AWS Course page.