I mean I am a noob at this domain exchange system, hell I just found out about this site today! So yeah I got no clue how much its worth
You have so much to learn. More than what I could write here but I'll do my best. I don't think you even have a grasp of what a domain name really is yet, but correct me if I'm wrong.
First and foremost, I haven't read about.me's terms but I am 99.9% sure it would be against their terms to sell your about.me portfolio address.
Secondly, the address about.me/index.html is a domain name + path, /index.html is the path and about.me is the domain name.
Let me explain how domain names work. When you type a domain name into your address bar (for example google.com), DNS (Domain Name System) is used for translating said domain name into an IP address that is needed for identifying the services/devices/servers to connect to.
We use domain names because they are more memorable and appealing than IP addresses.
The format of a domain name is [word(s)].[tld]. TLD stands for 'top level domain', these are at the highest level in the hierarchical DNS (Domain Name System). TLD's are classified into two categories; generic tld's and country-specific tld's.
When buying/selling domain names, you are always dealing with the part that is described above, for example namepros.com. You are not dealing with
https://namepros.com/some-page, because that is an absolute URL that is made up of many mandatory and optional parts; scheme, domain name, path, port, query string etc.
Anyway, hopefully this has given you a grasp of what we domain investors are dealing with here.