I have explained below clearly about this, If its still hard to understand for you then please search google “Adsense software udemy”.

Now let me explain you clearly.

Google doesn't release numbers, and publishers (i.e. the people running Adsense on their sites) are prohibited from sharing their CTRs, but...

You can get an idea looking at the problem backwards. In aggregate, the CTR for Adsense is the same as the CTR received by advertisers running Adwords ads on the "content network". (Adwords ads can appear next to Google search results or on other sites via Adsense. The latter is referred to as the "content network".) And, luckily, we do have some idea what the average Adwords CTR is--Google tells advertisers that 2% is a "decent" CTR.

Although that 2% refers to all of Adwords-- Google along with the content network--and many advertisers do worse on the content network (although some do better), I think it gets us in the ballpark. You also need to consider whether We're talking about the CTR for a single Adsense placement or the CTR for a page, which will likely have multiple Adsense placements.

Source : https://adsenseshop.com/forum2_theme_113253791.xhtml?tema=2&What-Is-A-Good-Average-CTR-For-AdSense