This was something I struggled with early on. I didn't really know what would be my calling.
At first I thought there were some "logical" paths. So I started studying for med school, and even though I wasn't excited about it, it felt like it made sense.
After some really hard reflection I felt this wasn't the best path and just started meeting with everyone I could. People from every type of industry and asking them what they do.
Over time I would get very drawn in to certain conversations and I'd realize that I was getting excited imagining doing the work they were working on. This is what I call "the pull", that intuitive excitement that is initially really hard to explain. I followed that pull, ended up starting a company that went on to raise millions and impact thousands of peoples lives positively and haven't looked back since.
TLDR: Talk to as many people as possible. When you start to feel excited about something, follow that feeling wherever it leads.