". . . I haven't a care in the world."
Hi, Jessy—I agree with Ahmed_btm. To expand a little on what he said, the main verb "have" (signifying possession) is capable of functioning as an auxiliary verb in British English (at least among older speakers of British English).
When the main verb "have" functions as an auxiliary, it works like the main verb "be." Both are capable of preceding sentential "not" ("It is not green"; "He has not the time") and of subject-auxiliary inversion:
It is green.
Is it green?
He has the time.
Has he the time?
In AmE, though, the main verb "have" is not an auxiliary verb. "Have" is only an auxiliary for us when it is part of perfective construction: "Have you been there?" The main verb "be," however, is always also an auxiliary.