Products with Giveaway Rights allow you to give them away for free. You can give such products away completely free on their own, or bundle them with other products you are giving away.
Many products with this right also have Master Resell Rights, meaning you can sell them, sell the rights to others to sell them, and give them away.
But remember that if you only see “Giveaway Rights” but not “Master Resell & Giveaway Rights”, you can only give away but can’t sell.
For more see: /what-is-r-private-label-rights-master-resale-rights-and-resale-rights/