Add gallery of tutorials divided by level

[Mr-Geekman]

Before submitting (must do checklist)

• [x] Did you read the contribution guide?
• [x] Did you update the docs? We use Numpy format for all the methods and classes.
• [ ] Did you write any new necessary tests?
• [x] Did you update the CHANGELOG?

Proposed Changes

See #1332.

Closing issues

Closes #1332.