If your IDE isn't providing autocomplete suggestions or underlining errors in red, then it needs to be configured.
IDEs evaluate your code as it is typed, giving you autocomplete, warnings, and errors. IDEs may also give you tips and suggest improvements to your code. They also come with a debugger, allowing you to see the state of your code as it evaluates. Coding without these tools wastes your time, and the time of anyone looking to help you.