Myself and wife went to Singapore for 3 days as part of our Honeymoon 10 years ago so might be slightly out of date however we really enjoyed a few things,
Fort Canning park - Beautiful park in the city an amazing escape from the hustle and bustle, We Walked around this park every morning with a iced coffee.
Little India. The food was incredible and cheap and so so many things to see including the Buddah Tooth Relic Temple.
There is also a free light show on the Merlion park over the water every evening and is well worth a watch for free.
Clarke Quay is a really nice vibe for evening drinks,
We also did the night safari at the Zoo and again really enjoyed it!
Sentosa Island is your go to for entertainment Cassios Theme Parks and beaches.
We also wanted to go to the Gardens on the bay but ran out of time... This still grates on both of us to this very day!
Make sure you go see as much as you can enjoy it pack an umbrella.
In regards to language you will get on fine.
Used the metro as its the cheapest and super efficient travel method!
Also take some time in the airport it's literally the best one in the world!
Have an amazing time OP im super envious of you!