Besides GSM antenna, WiFi and BT, can the phone contain 2 or 4 antennas for LTE, a GPS antenna, NFC, RFID and some do also contain internal antennas for FM radio and TV. A few phone models have internal ferrite antenna for AM radio reception.
Same antenna be shared for both WiFi and BT but it is not common. WiFi can have more than one antenna. For FM can the phone have one additional antenna for TX.
Wireless charging do also require a kind of antenna, even if it not is used for communication.
A basic phone have just one antenna, but it is often a multiband antenna, covering 2-5 frequency bands.