Turning a 60 sq m rooftop terrace into a garden: on the 11th floor, far from the city's noise, totally relaxed

I live on the 11th floor, and above it there is a 60 sq m terrace. After seeing the beautiful gardens that flower lovers online have created, I tried tidying up my own terrace too. The photos aren't great, so please bear with them!

Far from the city's noise, being able to have a little world of my own, coming to look at the flowers every day and occasionally zoning out, makes me feel totally relaxed

A grape trellis; I plan to plant wisteria

Summer temperatures are still pretty high! Luckily, my balcony faces east, so after noon there's no more sun

The terrace was done by a decoration company; the bonsai were gifts from others

I'm just learning to grow things, and they're all simple flowers and plants

I just don't know what would be good to plant, something easy to care for. I wonder if I can grow an apple tree, something to look at and to eat

Beautiful is hardly the word; I'm still learning to grow flowers, and I hope next spring will give me a riot of color!

It is a bit messy. I've just started learning to grow flowers and don't really know much yet, so I hope you'll give me plenty of suggestions!