Both approaches - call and email - have their pros and cons.
But bear in mind - no company hires anyone to teach them and letting them being payed while being taught. You should express your willingness and readiness for work not with words, but with actions and experience. Show the employer what you did your self do get ready for job, make an impressions of moving the learning path already.
In the regard email may really be a better option. You are given enough space to write down info about yourself and the employer will have time to review it.
In your case, the call conversation, especially with no professional or semi-professional background, will not last long.