If you are saying that the phone was not passcode protected, then anyone who picked up the phone could reset the device and set it up as their own, so the phone is gone if that is the case.
If the phone was passcode protected, then the data on the phone is safe, since no one could guess your passcode in less than 10 tries.
You have the information about how to try to locate the phone online......assuming that you enabled Find My on the phone.....but to do that you need your Apple ID and Apple ID Password to log on to www.icloud.com/find
Your Apple ID is probably your email address. Check the document below to see if that will help you remember the password.
If you forgot your Apple ID password - Apple Support
Otherwise, retrace your steps and ask at any restaurants or shops you might have visited before the phone was lost.
Good luck.