We have come to the Present Perfect.

It is now, but it is the result of something we did before.

We have come (HAVE + V3) to this place together.
We have studied (HAVE + V3) our Irregular Verbs.
We have learned (HAVE + V3) the Present Perfect.

So now, let's change Present Continuous Sentence to a Present Perfect Sentence. You can do it!

I am buying a car.
buy have had was bought has I
____ ____ _____ a car.

---