i think one website targeting one language and after that you can spread, best possible way may to use WPMU for the same.
As for promotion, you should have quality contents first on your website, once you have contents, get them shared on social media, also try to build some links yourself instead buying low quality links. Be careful buying ads
Try to optimize your website yourself, take care of Google quality guidelines and you will start ranking slowly
Jagan
ON Page SEO, Content Creation, Blogger Outreach and Brand Building Services
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