The array formula in cell C3 extracts the first character from first, middle and last name. The formula works fine with more or less names, up to 1000 characters. You can easily edit the formula if you need more letters.
To enter an array formula, type the formula in a cell then press and hold CTRL + SHIFT simultaneously, now press Enter once. Release all keys.
The formula bar now shows the formula with a beginning and ending curly bracket telling you that you entered the formula successfully. Don't enter the curly brackets yourself.
Explaining formula in cell C3
Step 1 - Split name into characters
The MID function returns characters from a text string based on a start number and the number of characters. The ROW function creates an array in this case that we need to split the text string into characters. The TRIM function removes leading and trailing spaces.