Here are some very easy exercises to practise the preterite (active and passive). If you surf the web, you’ll find more complicated ones, so don’t be shy and try!!
Regular verbs (Active form) : https://www.learnenglishfeelgood.com/fr/simplepast1.html
Irregular verbs (active form) :
https://www.perfect-english-grammar.com/irregular-verbs-exercise-1.html
Simple past (Passive ) https://www.learnenglishfeelgood.com/passive-voice-simplepast2.html