connected to the internet with modem?

with a cat 6 cable plus a connectors right into the phone.

Depends on what this means. That you have a modem does not mean you have a router.

Something needs to assign an IP address to your phone. Does the modem know how to do that for iOS? Can you log in to the modem from a browser on the phone?

My phone has a vpn with an ip. The fiber modem has a spot to plug in a cat 6 cable and a telephone cable. Should I plug in the telephone cable too? I know people have done this before.

No idea what you have. A modem does not necessarily have a router in it. A router is what provides connectivity to a device like your phone. Knowing what cables you have means nothing.

Do you not get support from whomever provides the modem?

I don’t know anything about fiber internet. It was forced on us by our phone company without any permission or information. Would it work plugged into a computer? I don't know if it would work with linux.

Again... nobody here can answer such vague questions.

Have you tried the website for your phone company? What have you tried to get your own answers?

The phone company guy said i would have no problem

Well.. that's not true right?

I am not sure if a router would work with this aweful fiber.

It must. Again, a modem brings in a signal that is typically paired with a router. Without a router, only a single "device" could connect to the internet.

Is there a reason you aren't naming this phone company? It's entirely possible someone here uses the same setup.

You have offered no details, for whatever reason, that could be used to help you.

Do you know how fiber internet works?

The fiber part is irrelevant. The signal inside your house is the same regardless of the technology used to get it to your house.

Satellite, Broadband, DSL, fibre... all the same coming out of the modem.

We have 3 phone wall plugins in the house and only one works. One of the bedrooms has one and when the fiber was off the line rang anyway. Its still on the copper cable. We had the answering machine on and it didn’t work. Interference. So not the same. Just the main one works. Thanks

Now you're talking about phone service, not internet.

Best of luck.