Udemy has a wide range of free courses in all categories. It is the best place for a beginner to learn anything without spending a dime.
Just search for free courses, you will find every course there.
It offers the best free online courses with Certificates than any other website. They are even adding new courses every week.
With my personal experience, I understood that Udemy had never compromised with the quality of free Courses compared to paid courses.
For a beginner, it is the best place to learn about any topic. Even Some Courses have 10+ hours of Course Content. Here you are charged for a Certificate.