When Impressions become Clicks
This is commonly refered to as CTR - Click-Through-Rate.
It is often seen as a measure of success for advertising campaigns but is more generally seen as an indication of how well you have targeted your desired audience.
Using GSC you will get reports of where your pages rank with respect to whether they are indexed, have been found by users making searches (impressions), the position in the SERP and finally whether the user actually clicked on the link to your page.
Ways to possibly increase your chances of a "click"
The reason that one of your pages receives an impression is that your have succesfully written a page that was found in the Google (or other search engine) that matches what the Internet user was looking for. If your site is high ranking in its own right or your page is toatally unique in its content (the domain name of your site will be unique and will be at the top of the SERP is a user searches for it), then the "position" will high in the SERP.
To increase your chances of getting a click will depend on how your page is described in the SERP.
The Title tag of the page will appear at the top of the impression and will be what the Internet user will see and make a decision on whether to click on your page. It is therefore advisable to make the Title as informative as possible. For example, this page is titled "When Impressions become Clinks"
Google say:
CTR is the number of clicks that your ad receives divided by the number of times that your ad is shown: clicks รท impressions = CTR. For example, if you had 5 clicks and 100 impressions, your CTR would be 5%. Each of your ads, listings and keywords have their own CTRs that you can see listed in your account.
Wikipedia say:
Click-through rate (CTR) is the ratio of users who click on a specific link to the number of total users who view a page, email, or advertisement. It is commonly used to measure the success of an online advertising campaign for a particular website as well as the effectiveness of email campaigns.