@Siddu9631,
This is possible, what I would do is:
1. Create a servlet (assetSizeServlet.class) that returns the size of any asset that lives in the DAM; servlet will only be used for the authoring environment.
2. Create new jQuery Validation Plugin, JVP, which will ping the servlet, passing in the path of the image; this will return the size of the asset, and your JVP's JavaScript business logic will display an error message from the toolbar as prompt.
This is an example of how a new JVP is created for a Touch UI experience, https://sourcedcode.com/blog/aem/touch-ui/aem-richtext-max-characters-length-validation. Take a read of this article, you can see, the JVP will validate form fields and display error messages.