Google has removed the concept of page rank instead of that you can focus on increasing domain authority. For that you need to build backlink for your root domain.
Create a robots.txt file
Submit meta data into the coding of the website.
Hyperlink social media site to yours
Make sure you are using H1 Headers in your website
Purchase an SSL certificate - Google will give you about a 15 percent boost just for that alone.
Goodluck!