Array notation and pointer arithmetic can be used interchangeably in C/C++ (this is not true for ALL the cases but by the time you get there, you will find the cases yourself). So although str is a pointer, you can use it as if it were an array like so:
char char_E = str[1];
char char_L1 = str[2];
char char_O = str[4];
...and so on. What you could also do is "add" 1 to the value of the pointer to a character str which will then point to the second character in the string. Then you can simply do:
str = str + 1; // makes it point to 'E' now
char myChar = *str;
I hope this helps.