Do i have to take oath of allegiance (verbal and/or written) with France while acquiring French dual citizenship through naturalization ?
There is a kind of ceremony during which new French citizens are given a “charter” of their rights and obligations. That's not presented as a condition for naturalisation and only happens after the decision has been made. I don't think you are expected to formally say or sign anything in public at this occasion and it's not even mandatory to attend.
On the other hand, the naturalisation process involves several interviews with various parts of the government (at least the relevant department at the préfecture and someone from the police, possibly someone from your municipality of residence as well). A lack of “allegiance” is actually a valid reason to deny someone French citizenship as “adhésion aux valeurs de la République” is one of the requirements. In theory, you are supposed to sign something to that effect during one of the interviews but based on what I heard from friends who became French recently, it's not always the case in practice.