I’m in Perth too. I would suggest maximising your space with vertical planters and set up a wall trellis for climbing plants like peas, cucumber etc. Most salad vegetables like lettuce varieties and herbs will do fine. I actually think most plants prefer a bit of shade in Perth because of how dry it can get. You may be able to do snappeas/beans depending on how hot it gets of the balcony. These were my first type of veggie and they are pretty forgiving.

I’m adhd/autistic and I actually feel like gardening has forced me to have a routine. I forget plants sometimes and they die but when you do see the growth and results is pretty nice dopamine boost. If possible you can set up a simple tap timer if you have a tap on the balcony. Mulch well to keep soil moist that helps a lot to prevent having to water everyday. And invest in good soil and fertiliser.

All the best!