Here are a few things from my side.
1. Talk to your customers. It is good to know how they think / see the product
2. Dig your competitors. Very much under-rated.
3. Lastly ask questions, keep learning.
As a relatively new PM, some things that I have found helpful:
1. Books: Inspired, Build, Hooked, Continuous Discovery Habits
2. Podcasts: Lenny's Podcast, In Depth
3. Communities: I joined a few slack communities and was able to make connections with more senior PMs.
Good luck!
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