Hi @Soumodip ,
Do you want to export your SP List into Excel?
Do you want to use Excel as data source within your canvas app?
For exporting your SP List into Excel, the answer is YES, you can. Currently, within a Excel file, you could own 1,048,576 rows by 16,384 columns in total.
Please check the following article about the known limits in Excel:
https://support.office.com/en-us/article/excel-specifications-and-limits-1672b34d-7043-467e-8e27-269d656771c3
More details about exporting data from SharePoint List to Excel, please check the following article:
https://sharepointmaven.com/export-sharepoint-excel/
If you want to use Excel table as data source in your canvas app, I think you would face Delegation issue in your canvas app. The Excel file is not a Delegable data source in canvas app, so it could only retrieve first 2000 records from your Excel table at most. In other words, if there are 5000 records in your Excel, you could only process first 2000 records in your canvas app at most.
More details about the Delegation in PowerApps, please check the following article:
https://docs.microsoft.com/en-us/powerapps/maker/canvas-apps/delegation-overview
Best regards,