There are 2 different votes on in the Security Council and one in the General Assembly. The GA vote will probably pass, there is no GA veto, but GA votes are non binding, so the PA will just get an upgraded delegation not a “state membership”. Only a SC vote in favor would admit the state, and Israel is counting on a US veto.
This gambit is really risky on the part of the PA. Israel is already a state member of the UN. Israel can always walk away from any territory it does not want to annex. This resolves nothing, only escalates tensions at a time when it isn’t needed or necessary. I believe the two sides could conclude a deal in principle in a week. The real problem is that the PA doesn’t really want to solve its own internal problems and so continues to project them onto Israel. If Israel agreed to withdraw to 1967 borders the PA would still not agree - they don’t want to deal with getting their own house in order.