how long should it take to cloud data onto a new iiphone 14

Without knowing things like the total amount of data to be transferred or the signal to noise and speed of the Internet connection, we cannot say.

Move the phone as close as possible to your Wi-Fi router and try to avoid using other Wi-Fi devices as much as possible until the download is complete.

Not to me. I'm sorry, but you really have no choice here. You don't want to stop or interrupt the transfer, so you have to let it go until it completes or until it fails and you see an error message.