I need help with this because I tried the script in termux but it didn’t take me to localhost:3000. Any help would be greatly appreciated.
Hi! Welcome to our community! 
Not sure what is Gandi. Host provider? =\
In order to install Rocket.Chat AND use it with android, you need to first, run rocket.chat, and second, configure a reverse-proxy that will deal with SSL.
The first step, you can do it with docs doc:
Once you are up and running with Rocket.Chat (usually on port 3000 at this stage) you can go ahead and configure the reverse proxy:
let me know if this helps 