Where do you live? First and foremost.
I already see a lot of people saying to just put some screen where the door panels are now. This is great if you live in a naturally humid place. If however your relative humidity is only 10-20% on an average day, then the screen probably won't do. Many people will make suggestions based upon what they have or what they do. It may be perfect for them, but you need to gather your personal data, and then plan accordingly. I live in Colorado at around 6,000 feet in altitude. The average relative humidity indoors during the winter while the furnace is running is only at about 11%. That is extremely low for the chameleon's needs. I must used a glass enclosure to keep the humidity high enough in there. I have a mist humidifier and a dripper running in the enclosure, and the plants and my chameleon are healthy. If I had a screen enclosure, I would need to run 2-3 humidifiers to keep the air moist enough for her, while making it unbearable for me and probably growing green stuff on the floor and walls from too much moisture.
Bottom line, you gotta do what's right for your home and it's atmosphere in order to make sure your chameleon get's it's needed humidity and temperature. I've seen generalized answers on how to humidify a chameleon's enclosure. They say all you need to do is spray the interior of the enclosure with a spray bottle twice a day. That does not address the relative humidity where you are. In the summer when our humidity level is only 3%, those 2 sprays would barely make it humid enough for maybe 10 minutes. You can't trust generalizations, because what might be good for that guy will not be good for this guy, and on and on. Make your decision based upon the end result being perfect for your chameleon based upon the conditions where you live. Remember to consider Temperature, Humidity, and Air Flow. By the way, it looks like your chameleon could have a great home. One last thing to maybe check into though. Did the maker of that furniture use any chemicals on the wood to repel wood eating insects, and would those chemicals hurt your chameleon?