I have had a couple of emails asking if it is OK to add additional layers, over and above the ones previously agreed. You do not need permission for this. As explained when the project was introduced, there should be one layer which your web map is clearly ABOUT, and that needs approval to make sure it is different from everyone else's. Other layers, usually including a base map such as Open Street Map, are included to provide context, and do not need to be approved. I have also just been asked whether you should include a list of references. You should NOT include a conventional set of academic references (and I do not know where you could put them). However, you SHOULD be using the ol.attribution function in OpenLayers to identify the sources for your mapping layers. See my Practical 1 instructions for an example of this being used not just to acknowledge the National Library of Scotland but to provide a hyperlink to their site.

As per the update, I have already replied to you 1 day back and done the task 5 days back ask your client clarify the point of API.

I have seen the video in the code he need to.insert the api for what he is asking because i have send inserted one api which was free so it has limited functionality if you can provide me paid one will update it.