Can i setup internet modem without a coax cable

Solution
A cable modem takes a coax input and converts it into etherent.
It does not know how to use any other type of input BUT coax.

Find out from landloard what options you have and/or if you can have the cable company instal a coax jack for service.
and depending where your located, some apartment building have agreements with a single ISp provider, some places are even fiber inside the building for ISp, yes talk to landlord to know if they have arrangements for ISP if not, ask cable company if they install internet at your location if not then DSL might.