The explanation of SSL that you’ve found is wrong.
SSL (Secure Socket Layer) or TLS (Transport Layer Security) works on top of the transport layer, in your examples TCP. TLS can be used for more or less any protocol, HTTPS is just one common instance of it.
HTTP is an application layer protocol.
In regular, non-encrypted HTTP, the protocol stack can look like this:
When using HTTPS, the stack looks like this:
- HTTP
- TLS (SSL)
- TCP
- IP
- Ethernet