I'll lay it out for you:

You take a given word (maybe when you start the program it accepts the
word as input)

The main program is a simple loop of accepting guesses until either the
user runs out of guesses (is hung) or guesses all the correct letters.

In the loop:

You accept a character as a guess
If the character exists in the word
   show it was a correct guess
   (display the character within hidden word for example)
else
   decrease the number of guesses
   (display part of the gallows if desired)

I did a solution in about 15 minutes. I read the word into an array of
char. I had another array of char of the same length which shows the
progressively revealed word (e.g. if the word was "hello" then it
initially displayed as "-----". If the person chose the letter "l" then it
became "--ll-".) When I check a guess, I simply look for the guessed
character in the first array of char (by looping over it) and in each
location I found it, I'd note the index and update the 2nd array of char
with the (correctly) guessed character at the same index. When the two
arrays are equal, then the game is finished (if you haven't run out of
guesses first).

Make an attempt and post it if you want more help.

Cheers

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