If u have a new Inspiron 3650 then it's not exactly an old putter ! When u say you live in the country are u suggesting there are no service providers that you can get dsl or broadband from ? Honestly dial up will work with windows 7 but the problem is gonna be using a pci based card in a computer that only has pci express lanes because they are not backwards compatible so your best bet would be to either get you a wifi hotspot and turn off 4g connectivity so it will utilize much less data per month and for 30-40 bucks you can get 5 gb on a prepaid hotspot which if u don't use a whole lot will be more then sufficient and even 3G speeds will be lightning fast in comparison to your previous connection dial up is pretty much useless on this pc
You could also use something like this m.dx.com/.../pci-e-to-dual-pci-riser-card-adapter-blue-419891 then you would have an extra pci slot in case you wanted to add another really old component card to your pc
Standard USB modem works fine with windows 10.
Old PCI modems will not have drivers for windows 10 and likely won't work at all.
HiRO H50113 V92 56K External USB Data Fax Dial Up Internet Modem Windows 10 8.1 8 7 Vista XP 32-bit 64-bit. Recommended use with PhoneTray, CallClerk, CallStation, DoorKing