I'm currently using Minecraft 1.15.2 and Using CraftOS 1.8 but when I use 6qmBBlpz Miner then type in Miner and select how many parallel tunnels, width, height, and length. Afterwards it allows me to choose if I want to use torches and chest but it won't let me press C or T to do so.

In Minecraft 1.13+, the codes returned by the key/key_up events have changed - see this page for more information. Therefore any comparisons against numeric values (such as line 192 and 479) will no longer be correct.

You'll need to replace the hard-coded literals with those using the keys API. This way they'll correctly work across all versions.