To select certain table you have to at first use ‘Get Table range’ activity and use its output as an input to Read Range activity. In each activity you have to specify sheet name.
You can offcourse build on it to make it quite generic so that you can specify a sheet and a table. A pseudo code would be:
Sheets = Workbook.GetSheets --> Generates a worksheet type output then
For each Sheet in Sheets
Sheet.ListObjects --> Gets Tables objects in a given sheet
For each Table in Sheet.ListObjects
Table.Name / Table.Item.Name (little unsure) ---> Get the name of the table
Use Get Table Range Activity with the sheet name and table name --> gets the range of the table
Read Range for the Table range
Modify it as required as UiPath Datatable
Write range back to the table