Someone else has already had that question
Whenever you have a question, and you’re not sure where to start looking for an answer, simply go ahead and ask Google. Some other person most probably has had the same question before, and often times you will find a helpful blog post, tutorial, documentation, or answer on community sites like Stack Overflow.
Finding the right terms to type into Google might take some time. Experiment with this. If one question does not yield a helpful result on the first page, try to rephrase your question. You’ll get better and better at this over time.
Always include the keyword “ruby” though, so you don’t get answers for other programming languages.
E.g. if you are wondering if there is a method that gets you all the keys from a hash, then google for “ruby hash get keys”. If you are wondering if there’s a method to align strings so they all have a certain length, then google for “ruby string align”.
Google results that link to the Ruby documentation on ruby-doc.org are often good ones to look at, but these pages also often are very long. Look at the summary of the page on Google, and the highlighted terms, then go to the page and use your browser’s search feature to find them on the page.
Also, results on Stack Overflow are often very worthwhile to read. This is a programming community site where people with all kinds of experience levels post questions, which then will be answered by others. People can rank answers, and the best ranked answer appears at the top. Often it is worth skimming through most of the answers, as sometimes the question asked is just slightly different from yours, but someone might still suggest a solution that might be similar to the one you are looking for.