I always seem to run outta food eventually or my Fisher keeps fishing turtles and they sit around and die and thats it.
Make farms.
Did, run outta seeds.
Make underground farms. First press "z" and go in the Kitchen tab. Disable Plump Helmets for brewing (so that Brewing becomes red colored for it). When plump helmets are eaten regularly, you get Seeds from them, but if they're brewed you lose the seed so you eventually run out. Plump Helmets are cheap, but they can basically feed your entire fortress for a very long time, at least until you start getting picky nobles that want prepared meals and stuff.
For fishing you need a FIshery to process whatever you catch, otherwise it will be unedible and it will sit there and rot.
For Hunting you need a Butcher's Shop in order to process the meat.
Also Rky you can keep your fort logs in here, I don't mind anyways.