how to make a discord.py command that interaccts with text not in command form code example

Example: How to setup discord.py bot

#Import essentials
import discord
from discord.ext import commands
import asyncio
#Some things that makes your life easier! (aliases to make code shorter)
client = commands.Bot(command_prefix='!') #change it if you want
token = 'YOUR TOKEN HERE' #Put your token here
#Making a first text command! (Respond's when a user triggers it on Discord)
@client.command()
async def hello(ctx):
    await ctx.send('Hello I am a Test Bot!')
#Tell's us if the bot is running / Runs the bot on Discord
@client.event
async def on_ready():
    print('Hello, I am now running')
    
    
    
client.run(token)