Hi @Abhishek Tripathi
Welcome to Microsoft Q&A platform and thanks for posting your question here.
To read nested .xlsx files in Azure Data Factory, you need to make sure that all the files have the same structure and sheet name. Then, you can use a "wildcard path" to point to the files in your dataset. This tells Azure Data Factory to read all the files that match the pattern you specify.
You can use the "Excel format" as a source in the following connectors: Amazon S3, Amazon S3 Compatible Storage, Azure Blob, Azure Data Lake Storage Gen1, Azure Data Lake Storage Gen2, Azure Files, File System, FTP, Google Cloud Storage, HDFS, Oracle Cloud Storage, and SFTP.
Reference
https://stackoverflow.com/questions/65906594/load-multiple-xlsx-from-blob-to-adf
I hope this information helps you. Let me know if you have any further questions or concerns.