First of all, that is not much of a subject line. It is clear from the fact that you are posting a question in the first place that you need help with something. The purpose of the subject line is to attract people who have expertise in the area where you need help, without them having to read your question first.
Second, you stated unnecessarily in your subject line that you need help. So there's [u]reall</u>y
no need to [u]re</u>state that in the body of your post...
I would loop through the entered word in a For loop:
Dim i as Integer
For i = 1 to Len(TheWord)
' then use Mid$(TheWord, i, 1) to access the character.
Characters have numeric value, their ASCII value. (For instance, “A” is ASCII 65.) If you are treating each character as only A through Z, convertng a through z to capital, you can dimension an array Dim TheArray(ASC("A") To ASC("Z")) As Integer, and increment the elements by testing the specific character's ASCII value with ASC(TheChar). If you are spanning the whole alphabet, both upper and lower case, You can make two arrays, and use an If statement in which if your char is between ASC("A") and ASC("Z") one part will be run that increments the right element in the UCase array, and the else part which is run if your char is between ASC("a") and ASC("z").
The incrementation can be
MyArray(Asc(TheChar)) = MyArray(Asc(TheChar)) + 1
You could have just one array, which would have what is essentially a void area between ASC("Z") and ASC("A").