You may search keywords for an article for [free] by accessing the below websites:
Google Keywords Planner.
Answer The Public.
Also Asked.
Google Auto-Suggestions [in Google search bar].
Quora.
Reddit Communities.
Social Media Groups [like Facebook and LinkedIn - see conversations and engagements]
Exploding Topics, and
Answer Socrates.
Pro-Tip: There are a few limitations to the above. Hence, you may utilize premium SEO tools like Ahrefs, Semrush, and Long Tail Pro [either of your choice] to find keywords [those with less competition] while writing article content that tends to rank higher in search engines like Google, Yahoo, and Bing.
P.S:
You are currently on the Digital Marketing Forum page; for more information on various topics that may be helpful, please visit Blog Posts (button below) and [share any content post you love] with your network.
[Best YouTube Channels for Learning SEO]
[Want to grow & stay ahead of your competitors? - use these e-Newsletters to your advantage!]
Are you with Trends? – Finding the [next big thing] just got easy
[If you have any specific questions in mind, please drop a mail and I will answer through a post at the earliest possible time]. Check this forum frequently for fresh posts.