Flights from EWR usually arrive at a Z gate but a B gate arrival is planned for tomorrow. Flights to TLV always depart from gate C13. Wherever the EWR flight arrives you will have a long walk to C (take the Skyline train to B/C first if you arrive in Z), with security between B and C, and an additional check for TLV flights before the gate.
If your layover is 2.5 hours it doesn't leave much time for a lounge and it certainly isn't worth paying for an hour in a lounge. According to
Frankfurt Airport's map there are some cafes and bars near C gates.