What would be a healthy drink that tastes like a (sweet) coffee but without caffeine?

Perhaps try roasted fig coffee substitute? It's definitely not coffee but has enough of the same roasty flavor notes to be passable. With milk and sugar, I probably wouldn't notice it wasn't coffee if I wasn't paying attention.

Depends on your definition of healthy and sweet. ‘Healthy’ is vague and fairly subjective. Plenty of coffee substitutes exist, such as roasted chicory-barley mixes that taste decent and provide you with some fiber. Is it healthy?

I've had a roasted barley drink called "Orzo" in Italian McDonalds. It had some of those same roasted/caramelized flavour notes as in coffee.

I should hope you're not being serious! In case anyone thinks this is real, decaf is not made from the dirt. It's beans that have gone through one of a few different processes. Swiss water method is what I prefer due to the low chemical processing.