Yes of course you can. These days all phones are required to do so by law so in case of any emergency you can use the emergency number to call the police or fire department.
You can use your windows phone normally but you can't use cellular features like calling or using the internet, however you can connect to the wifi and download apps or browse the net ...
I don't know if this can help but at least in Lumia phones in extra+info there is a "Manufacturer Name" and "Mobile Operator".
I think one of them can have information about the carrier and maybe it will tell you if it is associate with the carrier.
In my unlocked Lumia 920 I have this info:
You can see RM-821-lta-brazil_253 that maybe ...
The EAP info is kind of scarce. Some Nokia devices claim to support this starting with WP 8 like the 920 - spec but in general it is said that all devices updated to WP 8.1 will now support it. You can get the free developer preview for your phone now from here
That looks like a typo to me. Instead of the People app, open the Phone app and go to Settings, that's where the call forwarding option is.
For more information, see the official calling + messaging how-to.
Yes, there is a difference. Only the first SIM slot supports LTE.
I was using this device as SS device. When I used my SIM in first slot I had LTE and when using in second slot it was 3G only. I remember that I've checked max speed in setting and it was LTE for first and 3G for second slot. There are maybe different versions for Europe/North America/ ...
You cannot transfer your contacts to your sim card as of now. However you can use the Transfer My data app by Microsoft to transfer your contacts to another phone or take a backup to SD card.
You can find step by step instructions in here
In Windows 10 Mobile:
Go to Settings → Network & wireless → Mobile & SIM → SIM settings. Tap on "SIM applications".
In Windows Phone 8.1:
Go to phone settings → mobile+SIM → SIM settings. Tap on "SIM applications".
In Windows Phone 8.0:
Go to phone settings → mobile network. Tap on "SIM applications".
In Windows ...
You can download the user guide as a PDF. On page 7 of the linked guide you can see how to change the SIM card. Nokia suggests prying open the shell by putting your thumbnail in the seam between the screen frame and the
back cover, then bending the cover until it opens. A blunt knife might be helpful if you have troubles prying it open with your fingers.