G'day Anh and welcome to linux.org
Seriously, why would
we have it?
Take a look at the site you linked to, which says in part:
Support for Kali can be obtained via various methods listed on the
Kali Linux Community page. These images have a default password of “
toor” and may have pre-generated SSH host keys.
The default userid for Kali fully installed is
root
I cannot cay with certainty that that applies to the virtual images, but if it does, then it is
root
toor
If you cannot work this out, then you are very much
not up to Kali. Try an easier Linux like Ubuntu MATE or Linux Mint
any for 12 months to 2 years first, then see if you are up to Kali.
Hope you checked the sha256sums before or after you downloaded and before you installed.
Cheers
Chris Turner
wizardfromoz