I have installed Selnux as below and checked the selinux status was disabled but the task failed

yum install selinux-policy-targeted

yum install selinux-policy-devel policycoreutils

kindly advise

In the question it is supposed to be Selinux should be in disabled state after the reboot. So you need to check the config file.

Did you disable SElinux from its config file?

No , only installed the packages then checked the status
I will modify the config file once the task assigned to me again