I’ve spent some time studying Japanese and while I largely can remember how godan verbs are conjugated, sometimes I can’t remember how a ~ぬ verb works, or I mix up る godan with ichidan, or some other issue related to godan verbs. I have a chart that I made to resolve conjugation questions, but I really can’t rely on it all the time if I want to actually know this stuff. I find I need more specific reinforcement study for this, than Bunpro occasionally throwing some of the rarer verbs my way or not telling me if this verb is ichidan or godan and then leaving me to wonder why exactly my answer was incorrect (was it the verb, was it the grammar point, etc).
So what could I or someone else looking to improve specifically their godan verb understanding do?