If "Johnny went to town" is in A1,

=LEFT(A1,1) returns the first character of A1, "J"

=MID(A1,LEN(A1)-1,1) returns the second to last character of A1, "w"

=RIGHT(A1,2) returns the last 2 characters of A1, "wn"

The other text functions can be found through the Insert Function dialog box.