PHP - get current date, add years/months/days

get current datetime
    
        $dateTime = new \DateTime('now', new \DateTimeZone('Europe/Dublin'));
        echo $dateTime->format('Y-m-d H:i:s');
    
get current year
    
        $dateTime = new \DateTime('now', new \DateTimeZone('Europe/Dublin'));
        echo $dateTime->format('Y');
    
get current month
    
        $dateTime = new \DateTime('now', new \DateTimeZone('Europe/Dublin'));
        echo $dateTime->format('m');
    
get current day
    
        $dateTime = new \DateTime('now', new \DateTimeZone('Europe/Dublin'));
        echo $dateTime->format('d');
    
add years to date
    
        $dateTime = new \DateTime('2019-09-01 11:12:13', new \DateTimeZone('Europe/Dublin'));
        $dateTime->modify('+3 year');
        echo $dateTime->format('Y-m-d H:i:s');
    
add months to date
    
        $dateTime = new \DateTime('2019-09-01 11:12:13', new \DateTimeZone('Europe/Dublin'));
        $dateTime->modify('+3 month');
        echo $dateTime->format('Y-m-d H:i:s');
    
add days to date
    
        $dateTime = new \DateTime('2019-09-01 11:12:13', new \DateTimeZone('Europe/Dublin'));
        $dateTime->modify('+3 day');
        echo $dateTime->format('Y-m-d H:i:s');