Probably depends a lot on your home country and where you went for school.

In general, plenty of people still get jobs without networking, they're just likely worse than had you known someone. I'd recommend focusing on making professional contacts as soon as you get a foot in the door somewhere. Always take up networking opportunities like helping out new hires or meeting people from other offices if your company has distinct branches.

Getting your foot in the door is obviously easier said than done, but you can only move forward with your current situation so I'd not dwell on your lack of college contacts and just focus on making new ones. Also, if you really like where you're going to school you can always look into getting a job there.