const capitalizeString = (string) => {
return string.charAt(0).toUpperCase() + string.slice(1);

what is the meaning of above lines of code and string . slice .

Well, capitalizeString is a function that has a parameter called string, this function takes the first character of string and makes it upper case, and concat it with the rest of the string, and return the new string with first letter upper case

what is slicing is it any keyword or something

It is a method

thanx @ilenia now its okay, i got it