moment give in 2 days code example

Example 1: moment add 30 days

moment().add(30, 'days');

Example 2: momentjs number of days between two dates

var given = moment("2018-03-10", "YYYY-MM-DD");
var current = moment().startOf('day');

//Difference in number of days
moment.duration(given.diff(current)).asDays();