There are a few subreddits that might be helpful for you if you're looking for computer help. /r/BuildAPC is a good subreddit for starting out if you're looking to build a new computer. /r/TechSupport is another great subreddit for getting help with your computer. /r/AppleHelp is a subreddit specifically for Apple products.
If you're not sure which subreddit to start with, you can always try searching for your specific problem on Reddit. For example, if you're having trouble with a Windows 10 update, you could try searching for "Windows 10 update help" on Reddit. There are usually multiple subreddits that come up that can help you with your specific problem.