WordPress, an open source CMS, is released under the General Public License. Similarly, the default WordPress themes are also released under the terms of the license which gives you the rights to modify or redistribute them. Thus, there is no need for you to worry about that it is not legal to remove the footer message – “Proudly Powered by WordPress”.
Indeed, you are advised to remove the footer link which poses threats to your website security. If you want to learn how to get the job done, you can learn from
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