One thing I have learned I don't do enough is to just ask them. Learn about working out by asking muscly acquaintances. Learn about job applications by asking someone who works in the field you want to work in. Et c. Find a place that's suitable for talking and ask them to talk to you. People are happy to tell you all sorts of stuff they think you should know, and it's a way larger number of bits per minute than trying to infer what their lives are like from afar, or neutrally observing them like they're the subject of a nature documentary.
And then a key step 2 for getting advice on anything you have preconceptions about, actually consider that they can be right and you can be wrong. This isn't about following orders, this is asking various people for their advice in order to gain information, and then not throwing that information in the dumpster by only listening to people you already agree with.
Naturally this is largely advice to my past self, whose biases you (Dear reader) might not share.
One of the fastest way to learn is to learn from someone else's mistakes and experiences. This short-cuts a lot of unnecessary trial and error and can save significant time. However, one is sorely tempted to repeat the experiences/mistakes of others. One may think, that they are smarter/luckier than the others who made those mistakes. One may not trust that the right lessons were learnt by others in their experiences. One may think there is loss of agency in just following along a path someone else prescribed. What are some guidelines do you use to learn from others experiences? How do you judge their lessons are worth following? How do you stop yourself from attempting to make those mistakes yourself.