The list of plants that S Bengi lists and his explanations are good.
A food forest would include many perennial plants.
A food forest would mimic how Mother Nature would plant her plants.
For making a food forest, folks usually include layers.
There are 7 layers, including:
Tall Tree or Canopy Layer. This layer would consist of the tallest trees, most likely fruit and nut trees.
Sub-Canopy or Large Shrub Layer.
Shrub Layer
Herbaceous Layer.
Ground Cover Layer.
Underground Layer.
Climber, Vine or Vertical Layer.
For an added bonus these might be added, a Mycelial or Fungal Layer
Since the tree is so young I am having problems suggesting plants to add layers.
So I would suggest something like strawberries for the ground cover and a small berry bush to get your layers started.
Here are some threads to help explain layers:
https://permies.com/t/160695/Start-Food-Forest-Step-step
https://permies.com/t/61177/Planning-Layers-Food-Forest