If you are looking for free tools to remove background from bulk images, a few desktop-based software is available and two of the popular ones are RemoveBG and RemovalAI. The free version of the software though allows bulk removal of background but has limited support like 50 free previews and only 1 free credit. You can refer the tools to your friend and earn more credits. If you are looking for an online tool that can support bulk image removal, ClippingMagic is a good choice but the program is not free to use and you need to purchase the subscription depending on your requirements.