This one is a little bit tricky. Everything you need to manipulate individual characters in a string can be found in the text section of system expressions.
https://www.scirra.com/manual/126/system-expressions
You need each individual character of a word. The logic would go something like this:
Get the first letter of your word with left(word,1). You'll want to store that in a manner of your choosing, but I recommend pushing it into an array.
Then you need to take that letter out of the original word by setting text to right(word,len(word)-1). This means to set the text to the rightmost characters of the word length minus one.
Repeat until your word has no more letters (conditions- WHILE, len(word)>0).Now you have all the letters of your word individually in order in an array to work with.
Try working with that and ask again of you don't know how to proceed, as displaying the word again in pieces that can be manipulated and multiplayer are pretty complicated too.