As you are learning how to be a web developer, you need to challenge yourself with real clients and real tasks.
But you are not skilled enough yet to charge for your services, and you do not want to be rushed by a client who wants what they paid for.
We suggest you build 3 websites for free during your learning phase and use those sites as the basis for your portfolio.
A great way to start is to reach out to local non-profit organizations like churches, youth organizations, or charities. See if they need a website, or if they would like to replace their old site.
If you cannot find a non-profit, there are surely businesses which need sites built and would love to get one for free.
No matter who you choose, make sure you let them know up front that you are still learning. They should know there are limits to what you can do, and how fast you can do it.
Do not get into the habit of working for free. You’re learning a very valuable skill.