Advice for a new forever DM

Hello everyone, I recently got named the forever DM/GM for my group of friends because of my overactive imagination and ability to make up good encounters on the fly. But I'm having issues getting my friends to roleplay their actual characters. And no matter how many sessions or new characters we start they usually always end up being the same thing (headstrong murder hobos). Does anyone have any advice to encourage them to roleplay or to make the experience better?