You usually need to recreate parts of the target-school funnel yourself: understand the correct office and deadline, build relationships, and submit through the appropriate public or referral channel.
Look for alumni, recruiters responsible for your geography, diversity or affinity programs you genuinely qualify for, and events that are open beyond target campuses.
Do not assume a referral guarantees an interview. Its value is helping a strong application get context, not bypassing the screening bar.