can someone tell me how to get rid of these piano problems:
i go to hit one key and hit two
my left hand is very slow and stif

also could someone tell me how to increase my piano speed in both hand thank you

well i`m going to come up with the usuall piano answer to that :
tadaaaaaaaaaaaa PRACTICE
Stiff hands are normal when u start (same for hitting two keys at a time.. don`t worry happens to every, happens to me all the time... when i am tapping on this keybord of mine...) anyhow to unstiffen your hand do some scales with it befor starting to play a piece also do a pieces where it inables you to use that stiff hand of yours they have had a big talk about soliggietto (or some thing like that)on this forum, you will get all the info about it, so you could try that pieces (if you havent allready),it`s easy and fun to learn.
let me know what you feel

I know you were looking for an easy answer, but Svaty Pianist is right. Practice a lot, and those problems will start to melt away. I`m curious though, are you using a keyboard or piano? Because if you want to get really good technique I advise playing the piano because the electric keyboard gave me al kinds of bad habits, but maybe that was just me. Oh, and here`s a tip for practicing. Get an easy piece, then concentrate on playing it absolutely perfectly. Perfectly as in relaxed/loose wrists arms and shoulders, dynamics, rythmn, fingering, just... everything. It`s harder than it sounds.