Google does not use the keywords meta tag in web ranking
Why Webmasters Stack Exchange recommends it
Webmasters Stack Exchange answerers point people to it as an authoritative statement from Google that the meta keywords tag has no effect on ranking, so they can stop worrying about its length or content.
Recommended by 1 people across 1 different months, 2014 to 2019.
What it is
A short 2009 clip from Google's Search Central channel in which Matt Cutts, then head of Google's webspam team, states that Google does not use the keywords meta tag in web ranking. It accompanies an official Google Webmaster Central blog post on the same point.
What people said
Recommends Marek Andreansky · 2014-04 · Webmasters Stack Exchange · on “What's the maximum length of the meta keywords tag?”
Have a look at these videos from Matt Cutts, the head of Google's Webspam team: Google does not use the keywords meta tags in web ranking [this video] Should I spend time on meta keywords tags? [LINK] How much time should I spend on meta tags, and which ones matter? [LINK] more meta keywords info from the official Google Webmasters help Youtube channel [LINK] Why are you even considering this question, are you doing SEO for a local search engine that uses them? Please tell us your reason behind the choice so that we can help you more. As for the length, put any amount you wish - it really does not matter if there are 3 or 333 words in it.
Cites Khalil · 2019-05 · Webmasters Stack Exchange · on “Is it necessary for all the keywords in a meta keyword tag to be included in the page's content?”
For Google, it is not necessary to use a meta keyword tag. It won’t help in search engine optimization. It is seen as a spam signal rather than a ranking signal. Adding keywords to a meta keyword tag could also give your competitors an idea of what keywords you are using. So don't waste time on them and focus on quality content. Here is a video from Google webmasters [this video] Here is a blog post from google webmasters blog [LINK]
Cites Mnea · 2019-07 · Webmasters Stack Exchange · on “Know which keywords google has associated to my website”
To be honest, I wouldn't bother trying so hard to make SEs associate your website with the topic. I think it will come naturally, as soon as you show "signs of life" - add content (If i missed the page with content, I guess it's not indexed, than that is an issue as well). I mean, even adding meta = keywords means nothing to Google ( [this video] - matt cutts video). In the end, you have created this website for the users, not the search engines, correct? So, as soon as you get it through to people, sooner will SEs realise what your story is all about.