Digital marketing gives much opportunity to earn as freelancer. You being a student or a housewife can also earn good amount of money depending on your efforts.
Platforms like blogging, content writing, adwords management or having an adsense account can help you earning as freelancer.
In the beginning, you should take on whatever independent projects come your way, even if the compensation is low. Practical projects will help in understanding the tips and tricks of the trade and knowing clients’ expectations. You should try out projects of all kinds, be it an SEO project or a social media marketing project.