If you've never done SEO before, this is 70% of what you have to do on a page.
Pick a target keyword that you would like to show on Google for. Try not to choose something that everybody else is choosing, so just niche it down a little bit.
Put it in your page title. Meta description is optional. URL slug is mandatory.
H1 is mandatory. Beginning of the first sentence: half mandatory, but definitely try to do it.
Answer what the searcher is looking for right there before people start scrolling. Everybody thinks SEO is so complicated. It's really not.
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