I’m in a transition phase right now where I no longer desire to eat as much fast food as I usually have, and I’ve been cooking dinner more often. I’m not interested (yet) in doing anything culinarily significant – my best achievement to date has been cooking a pretty tasty top sirloin – but it would be nice to have a decently stocked kitchen to make simple, fast meals that consist of a bit more than a slab of steak.
As it stands, my kitchen is severely underequipped. I don’t have a lot on hand to throw stuff together, and what I do have isn’t necessarily nutritious. Being a neophyte cook, I know there are essentials one should always have on hand (tools, spices, ingredients) that are necessary to make a majority of simple meals, but I don’t really know where to start.
Toolswise, I have a rice cooker, two cutting boards (one for veggies/fruit, one for meat), a good non-stick skillet (though I’m considering looking for a cast-iron), and a few random pots and cookie sheets. Ingredients-wise, I’m clueless and usually don’t have much in stock.
I know there’s plenty of experienced cooks and chefs around here. What would you all suggest is necessary to always have on hand in the kitchen?

I’ve been avoiding dishes that require knifework as much as possible, but yes, I definitely need better knives than what I have now.