These are bilabial consonants, made with both lips.
We use [f] and [vl for the labiodentals (using upper teeth and lower lip) at the beginning and end of five.
Behind the upper teeth is a rough area (the alveolar ridge) where we make the alveolar sounds of [t in tot, ld] in dad, [s] and [z] size, and Inl in nun. Of course, there isn't always a match between written letters and phonetic symbols, as in the pronunciation of the sound at the beginning of photo and the end