Pretty M wrote:
My client has asked me to provide my sample through an upwork attachment. What does that mean? Can I not use the attachment option on the message window?
The attachment option on the message window is probably what your client means. I suggest you send it that way, and at the same time ask the client whether that's what they meant.
Sine you said this is a sample, I've assumed that it's not the end product of a milestone. If it was that, then you should submit the work product along with your request for payment.