This page holds the 'Getting Down to Work' stuff. There are pieces on basic writing and basic reviewing. Learning both is important if a beginner wants to improve their writing skills. I don't cover everything by any stretch of the imagination; you'll still have to find many answers on your own--and do a lot of practicing. But, reading and practicing what you find here will be a great start.
When you read advice saying, 'Reviewing others helps the reviewer become a better writer', don't brush it off as nonsensical--it's true. Reviewers see things in other writing that they miss in their own, and finding it makes it easier to spot in their own writing.
The more you learn about writing, and the more you practice what you're learning, the better you become. I've included many articles to simplify some of the mysteries of the craft--I hope they help.