hope this question doesn’t sound too vague.
I’m 5-6 years into my career now, and there are still a couple greybeard-level types I can ask when I run into a real puzzle, but the need to do so has been shrinking as the years have gone on; I’ve gotten better at finding my own answers. During my first job I was on two different teams where a mentor took me under their wing. These were people who I could turn to for design advice, technical questions, insight on best practices, etc. For me, as a curious and extroverted person, this was invaluable learning experience.
Your experience may be different, but to me it’s always good to have a solid group of people (coworkers, internet social network, even just stack overflow) I can rubber duck to or ask for input, discuss new technologies, learn from or learn with.
Coding a project of significant size is a collaborative process, and I think you’ll find that if you approach it with openness and curiosity, you’ll end up with mentors, peers, and mentees of your own at any given time.
“Standing on the shoulders of giants” is how I see it about my long line of mentors and after 4 decades in the software industry, I have become a mentor showing newbies how to diagnose legacy codebases
Mentors are essential, and more so today as there is too much information around design patterns, tools, processes, and working with management. A mentor sees trends and has a better handle on the rudder, for themselves and hopefully for these going before them
Seek them out and if they leave you knowing you know less, they have done their job