Don't think you've had no background or experience. You've had years of being around family, friends, classmates, teammates, in a variety of locations and settings. You can use any of that as long as you relate it to what the job is expecting of you.
There could be multiple ways you can think of answering to this question:
- Start from your most recent education experience.
e.g. "I graduated from abc high school in 2020"
- Use past projects to highlight your knowledge expertise.
e.g. "Creating a web application" OR "Organizing local college events"
- Past real world experience
e.g. "Volunteered online in abc.com to increase Covid awareness" OR "worked for abc company"
- One of your best projects where you got recognition
e.g. " Because of my Volunteering project, more people showed up for taking Covid vaccine" OR "I got recognition / award for my work with abc company"
- A 2-liner on why you want to leave your current job / interested in a particular role.
e.g. "I wanted to put my learning and knowledge into practical use in real world and this role will allow me to do just that"
Remember, this should be brief and should take you somewhere between 4 to 5 mins to walk through when you are interviewing.
Be confident in what you say. Do not add detail which you are not sure about or which are difficult to explain.