my device was stolen while unlocked, i want to block it and track it if possible.

Use any internet browser and log into www.icloud.com/find

Also see the following Apple articles for information about lost or stolen iPhones or iPads: If your iPhone or iPad is lost or stolen - Apple Support and

Find your lost Apple device or AirTag with Find My - Apple Support

If the phone really was unlocked, whoever stole the phone has access to everything on your phone.

You need to erase the phone as soon as possible......if it is still possible. If the thieves have already changed the settings on the phone, you won't even be able to connect to the phone using Find My.

Follow the instructions in this Apple Support document:

If your iPhone or iPad is lost or stolen - Apple Support

If the thief saw the password then there is no hope however if the password is unknown log onto your icloud and turn on stolen device protection as soon as possible. I hope you get your phone back!