For many products, license activation is an automatic part of the deployment process. Where user involvement is necessary for license activation, it is explained in the documentation for the product.
You might want to revoke a license. For example, you might revoke a license to return the cores to the available pool so they can be used elsewhere, or to purchase a new updated license to address an out-of-compliance system situation.
Depending on the deployment platform, you might need to revoke a license manually. Where user involvement is necessary for license revocation, it is explained in the documentation for the product.