I exercise every day to train my body.
風邪をひいて、体がだるい。
I caught a cold and my body feels heavy.
Specifically the main part of the body excluding the head and limbs.
体をひねって後ろを振り返る。
I twist my torso and look back.
Refers to one's physical build or body shape. Often used with adjectives like 大きい or 小さい.
彼は体が大きくて、力が強い。
He has a large build and is strong.
Used when talking about one's physical condition or health, often in set phrases like 体に気をつける or 体を壊す.
最近忙しくて、体を壊しそうだ。
I've been so busy lately I feel like I'm going to ruin my health.
お体に気をつけてください。
Please take care of your health.
I washed my body well in the bath.
I overworked myself and ruined my health.
He has a big build.
I try to move my body a little every day.
It's getting cold, so please take care of your health.
He trains his body at the gym.
身 is a more literary or idiomatic word for one's person or body, often used in set phrases, while 体 is the plain everyday word.
体 is the everyday Japanese word for the human body, while ボディー is often used for car bodies, camera bodies, or as a stylish loanword for physique.
心 (mind/heart) is conventionally contrasted with 体 (body), as in the common pairing 心と体.
体（からだ）is the everyday, casual word for the human body, while 身体（しんたい）is the more formal reading of the same kanji used in medical, legal, or official contexts.
Written with the same kanji, 体 read からだ means the physical body, a completely different word from 体 read てい meaning appearance or state.
body build; physique; figure
body (honorific)
all over the body; from head to foot; all over
body of Christ (Eucharist)
with one's whole body; bodily; with all one's weight