When opportunity record deletion i need to update the custom field on opportunity named as isdeleted__c and need to send this updated field to external system through outbound message. How we can achieve this?

When opportunity record deletion i need to update the custom field on opportunity named as isdeleted__c and need to send this updated field to external system through outbound message. How we can achieve this?

hi,all.
i am new here .
i want to combine process bulider and flow to complete that when i delete a record  ,the process will be trigger..can everybody help me?
for example , the Account object,i want to delete an account's case, when i delete it,it will trigger an outbound msg...
thx....