when am I going to become a YouTuber

The internet is your oyster! If you have access to a computer with internet, you can hop on youtube, and start looking around at different type's of video's to get a sense of the content you'd like to make. Be unique and try to capture a unique channel of interest.

The answer is up to you as far as when you'd gather the equipment you'd like to use, start with a channel idea then record the videos. My advice for equipment is to start with what you have which is a smartphone, come up with an idea and topic you are passionate about, learn how to edit the videos in iMovie and record!