Persuasive writing is a tool to get others to see an issue with perspective that is backed up by fact, and not just opinion.
Brainstorming words that go along with your topic is important.
Here are some resources that will assist you. You will be reading text to identify issues with arguments attached to them. You will be inferring what facts in these arguments can help your argument.
Britannica K-12 - Foundation information on many topics which can be useful in building an argument. NOTE: there are 3 Levels of information. Check all 3. The "listening" feature may help with understanding.
KidInfoBits - articles featured will often have a date attached. Sometimes that matters. If the information is too old,it may not be as helpful. Articles can be found here from the viewpoint of students making arguments for or against a topic. Some may be useful.
Newsela (Use Snap and Read to listen - icon in upper right hand corner)
Let's see what works. Use "sign in with Google".
Britannica Academic - search by topic in the "articles" link.
World Book - good overview on topics with links to "related topics"
World Almanac for Kids - good overview with connections