To see your Google Search Console average position, go to Google Search Console and in the left sidebar, click on "Performance." This will bring up a chart of your site's performance over the past 3 months. By default, it shows a blue line for total clicks to your site and a purple line for total impressions for your website.

Position is calculated top to bottom and then primary to secondary part of the screen (based on language). For English, that would be left to right but could be right to left for other languages.