Your MegaEsim plan connects to AirtelTigo, one of the main mobile networks in Ghana. You do not pick the network yourself. Your phone finds it and locks on once you turn the eSIM on.
AirtelTigo has good reach in the cities and most towns. You get a strong signal in Accra, Kumasi, Cape Coast, Takoradi and Tamale, plus the roads that link them. That covers where most visitors spend their time.