Work Garden Project

Hello! As the only member of my team even vaguely interested in gardening, I’ve inherited the work grounds as a side project. I’m only a beginner so wanted to ask if anyone had tips on how to transform the space?

It was previously used as a sensory garden and the bosses would like it to return to that. There’s about 12 beds marked out which are currently completely overgrown, as well as two planters, space along the entire lengths of the garden and a very large walk-in greenhouse. There is budget to get plants/trees/shrubs in.

There are some nice plants hidden amongst the jungle but I don’t know if anything is worth saving.

Does anyone have any tips such as: What to grow and where? What should I be doing this time of year? Any advice on someone just starting out in gardening?

Many thanks! ☺️