Here is how you would create a dictionary that contains a few key value pairs.

$mydict = @{"fruit" = "apple";
            "veggy" = "pepper"}

Write-Host Keys   = $mydict.Keys
Write-Host Values = $mydict.Values

Which should print the following.

Keys = veggy fruit
Values = pepper apple

Often, you will loop through the dictionary.

$mydict = @{"fruit" = "apple";
            "veggy" = "pepper"}

$mydict.GetEnumerator() | ForEach-Object {
    Write-Host key = $($_.Key) and value = $($_.Value)
}

Or like this.

$mydict = @{"fruit" = "apple";
            "veggy" = "pepper"}

foreach ($element in $mydict.GetEnumerator()) {
    Write-Host key = $element.key and value = $element.value
}

Which should now print the following.

key = veggy and value = pepper
key = fruit and value = apple