I've frequently travelled to school by bike in the last few years. Now I would like to start riding my bike just for fun, i.e. not only to get somewhere.

The problem is that I don't know how I can find any routes. If I had a specific location to get to, I could use Google maps etc. to find a route, but I basically just want to drive around somewhere.

How should I go about finding a route? Are there perhaps apps or online tools where I could enter how much I would like to travel (roughly) and I would then get a route which would eventually return me home (for context, I am primarily interested in small routes that can be completed in one to a few hours – not several days, for example)?

If it is relevant, I live in Germany.