Choose one correct answer [closed]
To describe someone who consistently shows respect for others, the correct word is respectful.
https://www.dictionary.com/browse/respectful
respectful
adjective
- full of, characterized by, or showing politeness or deference: a respectful reply.
The other words you suggest (respected, respectable) both describe a person who receives respect. (Although, hopefully, a person who shows respect toward others should and would receive respect in return.)
EDIT:
To apply to your original question,
"He respects everyone, so he is highly respectful toward all."