Hi Hiro
.
Using your definitions again:
1.
I have acquired / obtained (present perfect) =
In American English: "I have gotten" (I've gotten)
In British English: "I have got" (I've got)
2.
I have / I possess
(simple present tense) =
In American
and British English: "I have got" (I've got)
"I have gotten" is always the present perfect tense.
"I have gotten" is
not used to mean "I have" (I possess).