You can use Freepik icons for personal purposes, like creating your own website or promotional materials. They can also be used on, for example, packaging for professional use. However, avoid using Freepik icons as the main element for commercial products or logos associated with trademarks. Remember that Freepik assets are copyrighted to the company, and you cannot register an image that contains them.
Please, make sure to check Freepik’s usage rules.