Hi Mahima Kankriya,
Hope you are doing well.
As per my research, currently there is no Graph API endpoint to get the comments and likes of a site page in the document.
You may try to use SharePoint Rest API to get the comments.
To get Comments details:
/_api/lists/getbytitle('Site Pages')/items(pageID)/comments
or
/_api/web/Lists(guid'{listId}')/GetItemById({itemId})/Comments?$expand=replies,likedBy,replies/likedBy&$top=10&$inlineCount=AllPages
To get Like details:
/_api/web/Lists(guid'{listId}')/GetItemById({itemId})/likedBy?$inlineCount=AllPages
Liked by Information:
/_api/web/Lists(guid'{listId}')/GetItemById({itemId})/likedByInformation?$expand=likedby
Hope this helps.
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