Add a loop

Snowmelt

I added a loop to an existing steam, there where two water rads in a addition of the home. My question would be can I run an indirect water heater off an add a loop to a steam system?
2 nd question would be can you have multiple zones off an add a loop?
3rd an final question and this is thinking outside the box, would it be fessable to run an indirect off a steam boiler then run radiant off the indirect?