A tutoring business is one of the few businesses which requires a very limited budget in the beginning and has no limits in terms of growing the business.
People or students always need tutors to pass some important examinations or prepare for higher studies. A tutoring business is a highly demanding business and can be started with limited resources.
In the beginning, you can start a business alone yourself and can hire more tutors to expand your business anytime in the future.
Moreover, you do not always require a college degree to start a tutoring business. Many clients are willing to hire professionals with significant experience and skills regarding the subject.
If you want to be a solo tutor it's okay to work without a business plan. But if you want to expand and grow your business, you will need a business plan.