Hello Warrior Forum. Please Help Me With Some SEO Related Problem.

Heya,

I'm relatively new to SEO and recently joined a firm with a small SEO team. We do local posting and social media engagement for traffic and online presence. The company provide engineering services in the USA; I will only go into a few details -

1. We have a dedicated website.
2. We drive traffic from minimum off-page activities.
3. Our primary lead generation is from references and offline marketing.

Now my question is - the website contains pages for all the services we provide, say The MAIN PARENT PAGES; each main page has sister pages targeted at different locations in the USA. For example:
Main Page: XYZ Service
Sister Pages: XYZ Service New York, XYZ Service Virginia, and so on.

There are 250 sister pages around six primary service categories spread across the main pages. So a total of 1000 pages with the same content with only slight keyword variation.

What should I define as canonical for sister pages? The main page? Or the sister page itself? Currently, there is no set canonical on the sister page, and the Google Search Console has indexed around 5% of sister pages, with over 95% of pages defined as detected but not indexed.

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Please suggest to me what I should do next.

Regards.