I need help with an extremely simple Slack command app

Hey guys, I’m new here. I use Slack and want to make a simple command where when someone enters a command (ex: /manual), it provides them with a link (such as a google doc, etc.). Is Glitch the best way to do this? And if so is there an easy way to do this? Thanks!
Basically, I want a Slack command to give the user a link without anyone else seeing it, but it to work in a public channel.