It depends on what type of films she wants to make. If she really wants to learn the craft she will need to learn how to block and shoot scenes that contain dialogue. While GoPros are great for action and adventure they are very lacking in lens selection and the most basic tools you will need to tell a story involving humanity that speak.
She should spend some time really thinking about what type of stories she wants to tell and get the appropriate equipment for the job. Renting is not a bad idea to start as we use different camera's for different jobs.
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