Typically, one of the two selection buttons that are next to the big middle enter button delete stuff. On my phone, (pantech impact), on the front touch screen, its the right selection button. I have had nokia phones though and I beleive it is one of those two selection buttons. They are usually above the answer and hang up buttons.
Typing a number usually works by just holding the number key down, though most phones cycle through to the number if you keep pressing it
Making punctuation is usually assigned to the 1. pressing it once is typically a period and it just cycles through as you press it. Most phones have an insert symbol option that you can select it from there too.
On my phone to make a capital letter you press the pound button, though there is probably an option to chance the case in the texting menu
Spaces are usually the 0, but I've seen weird phones use the star too
you can use the direction pad to move the cursor around
Of course, I dont have the your phone in front of me so I could be wrong