Hints, tips and additional resources
Some easy puzzles have a hint panel on the left side of the IDE. Use it!
Each puzzle is linked to a specific forum thread. You can find tons of tips about each puzzle there.
Puzzles also have a presentation page with details about the problem, tags and possibly external resources links. Use them!
Most puzzles have been solved by hundred or even thousands of other developers, so it's higly unlikely that there is a bug in a puzzle.
99,9% of the time, the bug will be in your code and not in the puzzle. If you have an issue, double-check your code and search the statement for edge cases you might have missed.
Asking for help
Before asking for help, you can search for an answer here first. Most likely it's a classic issue and it has an explanation.
Then, you can ask other community members on Discord. People chatting there are quite friendly and will be eager to help. However, remember that they don't have to help you.
Not sure on how to explain your problem? Check out this guide on how to properly ask for help written by simon-tiger.
If you have a general question about programming, think about looking for an answer in the search engine of your choice. You'll most likely find an answer on sites like StackOverflow.com.
Finally, you can reach out to the CodinGame team via the contact page
After you solved a puzzle with a language, you can access solutions from other players in that language. You can learn a lot there!
For now, it's not possible to unlock and see other players' solutions without having solved the puzzle. Except in Clash of Code where players can choose to share their code.