I would like to share some points to update your old contents, these will help you to get new visitors on your blogs.
1. If your content is no longer relevant to a reader, either you can delete the page or add 301 redirect it to the highly relevant page.
2. The content should be actionable or useful to the readers. So, if there any ways you have, please add them (such as CTA, infographics, highlight the important points, add bulleting, videos).
3. Check your content properly and if there are any dead links, please fix them as much as possible. Because dead links create a poor user experience.
4. If your article discusses any specific year or time frame? see the possibility and make them evergreen by avoiding the exact time and dates.
5. If you have any translated article, please make sure the videos and images make sense to anyone reading the content in that language. Otherwise, we may lose our traffic and get more bounce rate to our page.