Type in either box and the other updates as you go. In Morse, use . and -, a space between letters and / between words. Write a prosign in angle brackets, like <SK> or <SOS>, to send it as one sign with no letter gaps.
A short press is a dot and a long press (about three times longer) is a dash. Pause about three dots for a new letter and about seven for a new word. The decoder learns your speed as you go, so keep your own rhythm steady.