How big is 10 lakh or 20 lakh? I am not familiar with this.
Anyway, most browsers will start having a hardtime rendering thousands of elements. Actually it really depends on how much CSS is involved, how deep is the DOM tree, if there are any JavaScripts hooks such as event listeners, etc. But as a rule of thumb consider a document with more than 10,000 elements a very hard one, specially in more underpowered devices such as mobile phones .
References:
https://developers.google.com/maps/documentation/javascript/overview (see the embedded video)
So if 10 lakh is greater than that I would suggest that you consider paginating your data.
https://laravel.com/docs/8.x/pagination#introduction
Also retrieving large chunks of data from an API endpoint can potentially put a heavy load on your database if there many concurrent requests to that endpoint.
Consider caching or saving this large dataset to a static file and serve that. You can have job or scheduled tasks that update the cache/static file from time to time.