Having some problems with the body and being unable to do things properly and easily, he quitted his job.
and是對等連接詞,連接的兩組文字要在詞性和文意的邏輯方向上一致。你給的文字有誤,要寫成上面這樣才合語法,句意才完整。to be unable to do = cannot do,不能沒有前面的be動詞。having要對上being,兩者都是「現在分詞」。
The meaning:-
(1)Having some problems with the body------participial perfect
and
(2)be unable to do things properly and easily--------means no power, no opportunity manner to do something.(adv clause).Will you be able to see that ? Hence "be" be added.
(3)the subject of the sentence not yet shown.