Tirana’s fleet of buses plies a total of 12 routes between about 05:00 and 22:00. Get on, pay the conductor 40 lek and away you go. It’s unlikely you’ll ever have to wait more than 10 minutes to travel on one, so at these prices and at this frequency, it would be somewhat impolite to complain. The city centre is so compact that the need to use public transport won’t happen very often. All buses are marked with their destinations, making them relatively easy to use. 
There's an excellent Tirana bus map, updated for 2023, available on the Transformative Urban Mobility Initiative website: https://transformative-mobility.org/wp-content/uploads/2023/05/SUTi_2023_05_04-URBANI-MAP_Tirana.pdf.