Yes, my dad does it all the time for his chowders and fish stews. Just get a fish frame (the head and vertebrate, whats usually left after they take all the fillets off) and simmer like beef bones. Its fishy, but in a good way (like how beef broth is beefy, but in a good way). Just like with beef broth you can simmer it down (reduce) till the taste is very fishy, or leave more water for a less fishy flavor. You can also add spices/herbs/veggies just like beef broth.
I'm not a big fish lover so I don't make fish broth but dad makes his the same way as beef broth: buncha bones (he likes to use one fish frame per 6 cups of finished broth and likes to get halibut frames from the butcher, sometimes salmon if he's wanting a very fishy broth), water, splash of vinegar. Simmer for 24+ hours. Strain broth to remove bones (he strains fish twice cause of how many small bones there are). Return to simmer and reduce till broth is as fishy as he wants it (which changes depending on what type of soup he's making). His chowders are amazing!