I am try get month and day but value is different o my text:
var fech = new Date("2021-02-28T00:00:00");
document.writeln("Year=" + fech.getFullYear());
document.writeln("Month=" + fech.getMonth());
document.writeln("Day=" + fech.getDay());
Result is:
Year=2021 Month=1 Day=0