It sounds like you only have the PlatformIO IDE extensions installed. There are detailed docs on how to link those to be usable as commandline, ahem, commands.
It’s really just a simple method of adding the extension’s binaries to your PATH environment variable. On my Linux laptop, it was a simple export PATH=$PATH:/home/norman/.platformio/penv/bin in my .profile file.
HTH
Cheers,
Norm.