Hi @Ilias Amhaouch !
IDs are generated sequentially by default and are never reused, i.e., if you delete the deal with ID 4, the next you create will have Deal ID 5.
Can you tell us a little more why you'd like these to be randomized? What is your end goal? You can create a custom field where you manually enter your own personalized IDs that you can generate with a random number generator. Would that work for you?