Hi, thank you for contacting JustAnswer.com. My name is Russell. I will do my best to provide the right answer to your question.
This is a fairly simple case, actually.
The phone ought to show something on its screen when you give it power. The phone line to your phone system does not have to be connected for that to happen... at least the phone's screen should light up, etc.
If it does not light up, check your power adapter for the phone. Also check whether you have it powered from a good outlet - or move it to where there is another outlet, and try to power it On without any phone line. It should light up, if not show something while starting up also (I have to be vague, since you have not said what maker/model the new phone is.)
If it still shows nothing, some part of the new phone is defective, from supplier/vendor/store, and it should be packed up and returned for a refund or an exchange, as defective-from-store.
(One additional point: if it simply lights up but shows a blank-screen, even when connected to a line, you may have a problem with the line itself. Try it on a different line, if that could be the case, to see whether the line is the problem, rather than the phone.)
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