What type of entertainment do you seek?
If it's night clubs then Arcardia beach is one of the main places and gets very very crowded.
During the day you can hire sun beds on the beach
Deribasavskaya street in the centre is full of restaurants and clubs.
Plenty of places to eat and many small shops/supermarkets where you can buy provisions.
Many restaurants have English menus. Best check
In the centre just near the train station there used to be a very large maket.
Don't know if it's still there.

GyuriFT

Please have pity on us who cannot read Russian. :-))))))

At least if I see a menu in English I have an idea of what to order rather than rely on my wife who has to translate and then describe.

When I am in Mykolaev I love to visit traditional Ukraine restaurants and indeed have noticed more and more have English menus to cater for the poor tourists!!

Great comments!!!