Chateau.
They type of French castle that begins with the letters ch and has seven letters is a chateau. A chateau can be with or without fortifications and is usually where someone of nobility resides.
Some French words that have "ch" in them include: Chocolat (chocolate) Chat (cat) Château (castle) Chanson (song)
A food in sandwiches that begins with ch is cheese.
Chimes ...
English 'begins' is 'commence' in French.
neptune
Chinstrap Penguin is an ocean animal. It begins with the letters ch.
cheese check checkmate chess chin
China rose Chrysanthemum
Chinchilla, chimp or chimpanzee
turd
Here are some cheeses that begin with the letter M:MuensterMonterey JackMozzarellaMascarpone