$confirmation = Read-Host "Are you Sure You Want To Proceed [y/n]:"
WHILE ($confirmation -ne 'y') {
 IF ($confirmation -eq 'n') {EXIT}
 $confirmation = Read-Host "Are you Sure You Want To Proceed[y/n]:"
}
ECHO OK

https://stackoverflow.com/questions/24649019/how-to-use-confirm-in-powershell/24649481