Usage of Present Perfect

According to what I've learned, Present Perfect has two main usages.
1) unspecified time before now. (there were five topics about concept of unspecified time : experience, multiple actions at different times, accomplishment, change over time, an uncompleted action you are expecting)

2) Duration from past until now (Non-Continuous Verbs)

First of all, does that mean nomal verbs can only be used only with first usage of Present Perfect?

Other tutorials say it usually has second usage.
And it seems to me that all of topics in the first usage
has relation with second usage anyway, but also it seems like all of them in the first usage is interchangable with Simple Past(Questiom two : is that true?).
I understood them as two different meaning having clear distinction between them, but solutions for ambiguous situation deciding whether to use SimplePast or Present Perfect often offer one rule applying to all of two usages.
Should I include the first usage to the second usage?