Capability and ability of PBNs-SEO

I have will to come at 1st position in google keyword "seo in india", I'm willing to do PBN SEO.
For this keyword
1. How much CF/TF metric contain expired domain should I purchase.
2. How much domain should I get so it will good for it.
3. So how much cost should I spend for it.
4. Using this PBN SEO In how many days I could be in first place on
5. Please recommend me to whom should I purchase High CF/TF expired domain.