As a student and early career astronomer myself, I've curated an extended list of references that I either look back to regularly or helped me get to where I am today. Different advice works for different people, but I hope some of these can help you:
Physical Constants and Astronomical Data
Matplotlib colormaps
Matplotlib colors
AASTeX author guide
LaTeX table generator
NASA exoplanet catalogue
The extrasolar planet encyclopedia
NASA exoplanet archive
TEPCat catalogue of transiting exoplanet properties
SIMBAD Astronomical Database
Sky & Telescope
Astronomy Magazine
Live Science
Science Alert
Astrobites
Today in science history
AstroBetter
Internships, REU's, and jobs
All NSF REU sites
Space Telescope Science Institute summer internship program
NRAO summer internship program
Yale summer internship program
ARL summer internships program
NASA internships
JPL summer internships
DOE internships
LANL internships
AAS job register
Major US fellowships for astronomy students
Brooke Owens Fellowship
Applying for graduate school
College departments offering astronomy related degrees
US and Canadian Physics and Astronomy graduate programs, their GRE requirements, and application fees
Jeff Asaf Dror's PGRE notes
Decolonizing science reading list
Whitening the sky: light pollution as a form of cultural genocide
AstroBetter: equal opportunity astronomy articles & resources
The antiracism starter kit
A guide to allyships
Anti-racism resources for white people
103 things white people can do for racial justice
How to actually promote diversity in STEM