How would I go about doing step $3$ in this excel assignment?

$1.$ Because some of the listings have no date of last review, they are missing data. To remedy this problem and still be able to include the listing in the analysis, replace date of last$\_$review with March $28,2011.$ Color the font in red so you know you inserted those data.

$2.$ There are also missing data for reviews$\_$per$\_$month. To remedy this problem, insert the value of zero $(0)$ if reviews$\_$per$\_$month is missing. Color the font in red so you know you inserted those data.

$3.$ Calculate a variable called EntDum $($a dummy variable that can carry the value of $1$ or $0,$ which equals $1$ if $$room$\_$type$=$Entire House$$ and $0$ if $$room$\_$type$=$shared room$$ or $$private room$).$ To do so$,$ sort the database by room$\_$type and insert a variable and name it $$EntDum$.$

$4.$ The borough of Manhattan in New York is an important area for tourism, and it may well command a higher price for Airbnb rentals than accommodations in the other four boroughs $($Brooklyn$,$ Queens, Staten Island, and the Bronx$).$ Create a new Manhattan dummy variable $($a dummy variable that can carry the value of $1$ or $0)$ that equals $1$ if neighborhood$\_$group $=$Manhattan$$ and zero $(0)$ otherwise