Hi, Wael Shaltoot,
I do know that"when" can work as a preposition.
No, "when" is always a conjunction.
Is it correct to say"When meeting Tom,I was walking home".
No, that is not correct. You could say:
- When walking home, I met Tom. (I strongly prefer "while" in this case)
Can "When" work as a prepostion or be part of an abridged adverbial phrase with all tenses?
"when" can introduce abridged adverbial clauses, usually — if not always — when the verb be forms part of the full verb.
- When/While (I was) walking home, I met Tom.