Hi Liana.
If you create and confirm a PO the status of the PO will be "Confirmed".
If your PO has one line and you cancel the full quantity of that line before doing any receipts, the status of the line and thus PO will be "Canceled".
If your PO has one line and you partially receive it, e.g. your confirmed PO had 2 qty. of a unit and you receive 1 quantity of this unit. This will leave both the line and header status as "Open", as there is still pending delivery remainder transactions.
If you cancel the remaining 1 qty on the PO, so you will have 1 qty received and 1 qty canceled on your PO line, this will change the status of the line and thus the header to "Received" as there is no delivery remainder left.
Once you start invoicing the PO, the status will obviously change to "Invoiced".
I hope this clarifies the questions you had around PO statuses.
For more details you can check some of these threads for PO cancellation and partial delivery updates.
BR
Nikolaj
