Apparently it is supposed to be part of Python3 but it says "bash: sqlite3: command not found". 
I'm so new to all of this and I'm just trying to follow along with a tutorial on youtube. Any help would be much appreciated.
On Linux (or in a Docker container running a Linux OS variant), you can install the command line interface via sudo apt-get install sqlite3 and then run sqlite3.
bash: sqlite3: command not found