At Once
Right Now, Immediately, Right Away
adverb
You'll have to learn this word in two parts. You already know the meaning of 今 because of the kanji, which means "now." The すぐ part, however, is a new word, meaning "soon." The two words even start with the same "soo" sound. If you put these two together, you get "now soon." Put in better English, that's at once or right now.
いますぐ
Since you already know the vocab word 今 (read いま), you should be able to read this word as well.
今すぐ、会いに行きましょう。
Let's go meet them right away.
いいから黙って今すぐ来い!
Be quiet and come over at once!
花火は今すぐにでもスタートするよ。
The fireworks will start any minute now.