Did 1999 Subaru Foresters have carburetors (and could that be my issue)?

around 1985 86 carburetors were replaced with fuel injection or a TBI unit which is basically a carburetor with an injector on top , extra fuel is needed when the engine is cold a sensor tells the computer to pulse more fuel , it is a narrow air fuel mix that works best under different conditions if it turns over (cranks) the batt. and starter are good , if it starts and there's a batt. icon on the dash the alternator is no good , if it doesn't start when cranking and you spray starter fluid down the throttle and does not start then you probably have no spark

Fully electronic fuel injection. First, does it crank? Then look at the small water temp sensor that screws into the manifold just under the throttle body. It's under $20 and an easy swap if you can a socket on it. If it doesn't crank remove and thoroughly clean both battery connections, as that brass one easily cracks and loosens; you may have to replace it with a generic $2 alloy one. It is EXTREMELY unlikely that this F needed a starter; if it was replaced then check its connections too. The aforementioned water temp sensor tells the ECM to send extra fuel through the throttle body to cold-start. In that sense it acts like an old carbureted "choke" system...but otherwise it's completely different. If the sensor fails the ECM doesn't know the coolant (ambient) temperature. It has one wire coming off it, and appears from the back a bit like a spark plug. I'm betting your original brass battery positive clamp is a corroded, cracked mess....