Press the + button on main page of the app.
Press Excel icon to open file selector page.
Open navigation menu from left to see more folder options. You can select file from like Google Drive, internal storage of phone, downloads, etc.
If you can't see internal storage folder, press the 3 dot menu on top right corner and select Show internal folder.
Select an Excel file.
Create table page will open where you can define the column types, no. of columns and no. of rows to be imported.
Press tick icon on top right to import the whole data into the table.