MandatoryParams.ps1

function Do-Something {
    param (
        [Parameter(Mandatory = $True
            Position = 0)]
        [string]$Param1,
        
        [Parameter(Mandatory = $False,
            Position = 1)]
        [string]$Param2
    )
    
    $Param1
    $Param2
}

function Do-Something {
    param (
        [Parameter(Mandatory,
            Position = 0)]
        [string]$Param1,
        
        [Parameter(Position = 1)]
        [string]$Param2
    )
    
    $Param1
    $Param2
}