As google is classifying more and more links. Like adding categories. Should I be doing that for my internal links too? I mean adding all the attribute types?
You don't need to add any attributes in your internal links. Just leave them as normal links with anchor texts.
And why would you want to make your internal links no-follow anyway? It will only make you loose your link juice without making a profit out of it.
Using no-follow tag isn't advisable because doing so will lose the chance to get benefited from the link juice which is very helpful to improve your SERP ranking.
Why would you want to make your internal links no-follow? And forget about the attributes they are for outgoing -external links.
Just leave them to be.
No need to do this for the internal linking.
Don't use the no-follow tag in the internal linking. It's not beneficial for the internal link.