I'm developing a web application now, and I want to set to starting Google lens if the user click the icon in web browser on Android smartphone.
How can I code <a href=""></a>
on html?
I'm not sure I understand your question, but I don't think that Google Lens offers an API for things like that.
You might want to take a look at Googles machine learning kit: https://developers.google.com/ml-kit/