Defining Resource wise nonworking days


I have been exploring the smartsheet and so far it looks okay. But I could not find one major feature here which is (should be) present in any other project management tool. I was looking for the option for defining Resource wise nonworking days but was unable to find it. e.g. John is a resource in my project and he will take the personal time off (casual leave) on 11/18/2020 and 11/23/2020. I want to give entry of these personal time off somewhere in the smart sheet so that during scheduling these will be excluded. Can you please let me know how to achieve this in the smartsheet?

For better understanding here I am attaching a screenshot from MS Project where I can manage resource-wise personal time off.