Mentoring can be a challenging job. However, if a tutor understands the challenges they may face, overcoming each obstacle is much easier. Each student arrives at the tutoring sessions with some prior knowledge, experience and skills. Is it difficult? I'd say no.
It's easier than teaching 30 kids the same thing at once. However, it requires you to have a good command of the subject and a way to fill in the gaps if there are gaps in the student's knowledge. Working one-on-one with students requires immense patience. You have to learn to adapt your teaching and classes to adapt them to different learning styles and different curricula.
You will have to spend part of your free time preparing for upcoming classes and sessions.