Give it some food and get the light as close as you can to it.
Maybe even consider something like this if your on a tight budget
https://m.youtube.com/channel/UCDqXe9FP6RAx6_WbgHYzlnw
Good luck and don't give up
Best to use ducting to bring air in and its best to have an air filter (or sock in my case) to stop bugs and dust.
Yes you will self your plants if light leaks in.