i install esxi 8.0 set the default root password but when I try to login with the default root password it's telling me the password is wrong
How did you set that root password?
What I can think of is that either you entered a password, but selected the wrong keyboard language mapping, or you installed the ESXi host using HPE's "Intelligent Provisioning" which sets the root password to "_Passw0rd_" (see https://support.hpe.com/hpesc/public/docDisplay?docId=a00112754en_us&page=s_config-os-setting.html).
André