Fresh theme only has two levels of menu - if you need more you can use the Modern or Bootstrap theme (with a side menu) to get more.

However, another option could be to create the lower levels using a Filtered Item List or similar includelet.

For example the Website Features box on the demo site, here: https://e-voice.org.uk/demosite/

Or if you have lots of content that can be categorised, you can do somethign like the Latest section on the Superhighways site, here: https://superhighways.org.uk/latest/

Hapy to advise on how you can create an appropriate section if you give us a bit more idea what you want to achieve.

Cheers

Joe - Voice Admin