One way to come up with popular topics for your blog is to do some keyword research. You can use tools like Google AdWords Keyword Planner and Google Trends to see what keywords are being searched for the most. You can also look at competitor websites to see what topics they're writing about.
Another way to come up with popular blog post ideas is to see what's trending on social media. You can use tools like Twitter trends and Facebook Insights to see what topics are being talked about the most. You can also try searching for hashtags related to your industry on Instagram and Pinterest.
You can also look at news sites and online publications to see what's being talked about in your industry or niche. This can give you some great ideas for blog posts that will be relevant and timely.
If you're not sure what topics would be popular with your audience, you can always ask them! Send out a survey or poll, or post a question on social media or in a forum related to your niche. Your audience will be happy to tell you what they want to read about, so you can give them exactly what they're looking for.