Every set of exercise has a target range of repetitions. For example, a 3 x 8-12 or simply a 3 x 10 set - the standard set for muscle growth because Hypertrophy is Optimal at 8-12 Repetitions.
These sets should use a moderate weight (around 75% of the 1-rep maximum) such that you reach muscle failure - meaning you couldn’t execute another repetition no matter how much you wanted it.
Muscle failure will happen sooner in consecutive sets, so adjust your initial sets to failure slightly above the repetition target (e.g. failure at 12) so that the later sets won’t fail too far from the optimum (e.g. failure at 8).