I am trying to configure browser caching with my NGINX config and don't know how to do it

I am trying to update my browser caching expiry periods to 1 year as recommended. It says my server type is Nginx. The setup instructions are confusing to me and I don’t know how to do it. Step #1 is:
Copy the generated code into your nginx.conf usually located at /etc/nginx/nginx.conf or /usr/local/nginx/conf/nginx.conf
And i have no idea what that is or where to find it. Can you please help me? Thanks!