What's the difference between "i like you the most" and i like you best"?
as subject, what's the difference between these two sentence, and how to use them properly?

Question

Answer

Very similar phrases, both are comparisons. I strikes me that the first sentence is based on quantity and the second based on quality.
I like you the most - more than any other i.e. more than/less than
I like you best - better than the rest i.e. good/better/best

Answer

I think they are interchangeable.

Answer

"I like you the most" can be used by itself, or can be put into a 'selection' context like: "out of all the teachers, I like you the most".

"I like you best" does not make sense by itself.  Rather, it needs to be qualified further like: "I like you best when you're not angry."

Answer

i like you the most = upon everything or everybody else
i like you best = upon the ugly neighbor ( just kidding, upon a specific person)