Reflexive verbs in French are verbs which mean an action done to oneself, for example, laver means 'to wash', but se laver means 'to get washed' or literally ‘to wash oneself’.
Reflexive verbs follow the normal formation patterns and many are regular -er verbs. They just have an extra pronoun.
Here’s an example with se laver in the present tense:
French English
Je me lave I wash myself
Tu te laves You wash yourself
Il/elle/on se lave He washes himself/she washes herself/we wash ourselves
Nous nous lavons We wash ourselves
Vous vous lavez You wash yourselves
Ils/elles se lavent They wash themselves
Remember that me, te, se become m', t', s' before a vowel ( source BBC)