My iphone lost.i coudnt find my lost phone location

I'm not sure what you see when you go to Find My. If your phone is not listed, FMiP was not turned on. If it said offline or no location found then it means battery died, no internet connection or device not turn on.

Then your options are mark at lost, erase device or remove it from your account. Remove from account means disable FMiP on that device, so if someone find it and erase the device, it will not attach to your account and information anymore and they can use the device as new. For mark at lost and erase device, you can request it and then it will successfully enable when the device is turned on and connected to internet. If your device has passcode lock, no one can get inside it and the only option will be erase the device, but as long as you have FMiP turn on, the phone will be locked to your account and the person who found it cannot use it.

Find your lost iPhone or iPad with Find My - Apple Support (CA)

Did you turn on Find My and Send Last location? Anyway if your device is lost or stolen, mark it as lost immediately

Find your lost iPhone or iPad with Find My – Apple Support (UK)

DON'T remove it from your account, if you do remove it anyone that finds it can reset the iPhone and keep it as theirs