You don't need to know it all
Being a product manager in an enterprise context is different. PMs think they need to have all the answers, but the truth is you can't know everything in complex enterprise organizations - and that can be your strength, not a weakness.
Your value isn't being the expert on every technical detail or business process. It's synthesizing what you do know, being transparent about gaps, and asking the questions that unlock insights from people who do have the answers, building a coalition of partners along the way.
The best enterprise PMs I know over-communicate what they've learned and under-promise what they know for certain. They turn "I don't know, but let me find out" into a competitive advantage.