DataCamp
Browser-based courses with an inteactive console for learning data science and analytics. If you take APSTA-GE 2352: Statistical Computing class, you’ll get free access.
RDocumentation
The best web-based source for R libraries and function documentation.
R-bloggers
Blog posts on almost any R-related topic.
Stack Overflow and StackExcahnge
These are self-evident. Just google your computing question and Stack Overflow or StackExchange are bound to be in the top five results.
stackoverflow.com
stats.stackexchange.com
R for Data Science
Free book on how to use R, by Hadley Wickham and Garrett Grolemund.