how can i contact and chat with the apple support

Apple doesn't help with or get involved in lost or stolen devices. Contacting them for help would be pointless. All they will tell you is to use Find My to try to track its location. But as KiltedTim correctly points out, if it is powered off, the battery is dear or they have put it in a bag which blocks it from connecting with a network, its current location cannot be found.

Contact your carrier and ask them to blacklist the phone. If you get a message your phone has been found, and they ask for proof of ownership, such as Apple ID and Password, it does NOT come from Apple, but it does come from clever thieves, who hope to trick you into giving them the information they need to wipe the phone. DON'T FALL FOR IT.

The sad reality, very very very few stolen phones are ever found.

The only way to track it is with Find My. If it’s been powered off or the battery is dead, placed in a faraday bag, or otherwise does not have a data connection, there is no way to locate it.