@AKumar123 it seems to me that you had password protected your keystore when you ran elasticsearch-certutil so you will need to the following commands, one by one, wrote the password you defined for each and then restart the elasticsearch instances in the end:
bin/elasticsearch-keystore add xpack.security.http.ssl.keystore.secure_password
bin/elasticsearch-keystore add xpack.security.http.ssl.truststore.secure_password
bin/elasticsearch-keystore add xpack.security.transport.ssl.keystore.secure_password
bin/elasticsearch-keystore add xpack.security.transport.ssl.truststore.secure_password
Also be sure you have defined the location of your .p12 files correctly both for master and the node.
You can find more info in a similar issue Problem with keystore password was incorrect or a complete guide on https://www.elastic.co/guide/en/elasticsearch/reference/7.8/configuring-tls.html