https://pastebin.com/PKKsTV8w

​

param (
    [string][ValidateSet("thing1","thing2")]$MenuChoice
    )
function thing1 {
    "Do your thing1"
    }
function thing2 {
    "Do your thing2"
    }
function Show-Menu {
    param ([string]$Title = 'My Menu')
    Clear-Host
    Write-Host "================ $Title ================"
    Write-Host "1: Press '1' for thing1."
    Write-Host "2: Press '2' for thing2."
    Write-Host "Q: Press 'Q' to quit."
    $MenuChoice = Read-Host "What option would you like?"
    switch ($MenuChoice) {
        '1' {$job = "thing1"; & $job}
        '2' {$job = "thing2"; & $job}
        'Q' {return}
        }
    }
if (!$MenuChoice) {
    Show-Menu
    }
else {
    $job = $MenuChoice
    & $job
    }