In Senegal this eSIM runs on the Tigo network, also known as Free Senegal. It is one of the country's main mobile operators and it carries plenty of 4G across the cities. Your phone picks the network on its own once the eSIM is turned on, so you do not need to choose anything by hand.
Tigo is strongest in and around Dakar. The capital, the suburbs of Pikine and Rufisque, and the busy Plateau district all get a steady 4G signal. Thiès, the second city inland, is also well covered. If your trip stays in these areas, you will rarely lose service.