I want to add SSL certificate using AWS Certificate Manager for my website which I created using a Wordpress instance on EC2, hosted the domain with Route 53.
Unfortunately a public ACM certificate can not be deployed to your individual EC2 host. It must be attached to one of the following options:
If you are able to put your instance behind one of these you'll be able to use your ACM certificate.
Outside of that ACM does support private CAs that can be deployed to resources but they do cost $400 per month for each CA.
Alternatively if you want to have a free SSL, using only an EC2 instance I would suggest looking at [certbot].
AWS has created a tutorial for setting it up here.