The most conventional job to get: school or direct application. However, most project managers entered consulting firms after school or MBA as Business Analyst or Associate. Entering directly as Manager is harder.
Most straight-forward path is to go through on-campus recruiting from grad school. This typically puts you at an Associate position. After ~2 years of solid performance, you can progress to Engagement Manager.
If you do not have access to on-campus recruiting, you can sometimes go through websites. But much more of a "black box" process.
Expect to work 3-5 years as a Consultant, while performing the tasks of a Manager for ~6 months prior to actually getting the promotion. It is extremely difficult to transition to the Manager role without prior experience as a senior strategy consultant (Consulting culture is unique and you'll need mastery at using a hypothesis driven approach to avoid boiling the ocean, etc)
More than your resume, hiring managers want to see the thinking you'll contribute day one.
Learning about the types of jobs that exist shouldn't depend on who you know. You can change that.