Welcome to the Bunnings Workshop community @Soana. It's wonderful to have you join us, and many thanks for your question about installing blinds on Mimosa gazebos.
These semi-permanent gazebos are engineered to a myriad of different specifications, including everything down to the thickness of materials and the way they are fixed to concrete. They are designed to have no walls so high winds can pass through them. In fact, it's a requirement that the louvres be opened in high winds, so the roof doesn't become a sail. If you were to install blinds or walls on the gazebo, they will inhibit the ability of the structure to perform as intended by not allowing wind to pass through it. This will place immense amounts of force on the frame, and it is not designed to cope with these additional stresses.