Tenerife Sur (TFS) handles most international flights to the south-coast resorts, while Tenerife Norte (TFN) near Santa Cruz/La Laguna serves domestic and inter-island routes — check which airport your itinerary needs, as they're over an hour apart.
A rental car is the most practical way to see the island beyond the resorts, given how spread out attractions like Teide, Masca, and Anaga are; roads are well maintained but mountain routes are narrow and winding.
The Titsa bus network covers the whole island affordably, and the Tranvía tram connects Santa Cruz and La Laguna every few minutes — useful for that specific route without a car. Taxis are metered and reliable in town but expensive for longer cross-island trips. Inter-island ferries depart from Los Cristianos (to La Gomera) and Santa Cruz (to Gran Canaria and other islands).