This is an older one but still one of my favourites.
At https://command-not-found.com/ you can find any application that belongs to your “not found” terminal command.
Furthermore it tells you which command you might want to install the application with on your specific OS.
This is a special one because
nslookup is available in different packages dependent of your OS distribution.
$ nslookup dibi.dev
Hit https://command-not-found.com/nslookup and you're good to go.
There is even a Zsh plugin available that includes the results directly into your terminal.