Selecting text within a cell works in the same way as selecting normal text with the mouse. For more information, see Selecting text and objects.
To select complete table cells and their contents, proceed as follows:
Selecting via the mouse
▪Select the entire table or table area: Click in the first cell to be selected and then drag the mouse with the mouse button pressed to the last desired cell.
▪Select entire columns/rows: Click in the area directly above a column to select the column. To select a row, click in the area directly to the left of the row.
▪Select a single cell: In rare cases, you only need to select a single cell. This is done via the following "trick": Drag the mouse cursor from the cell you want to select to an adjacent cell and back again.
Alternatively, click in the table cell with the mouse and then press Shift+à to select the entire cell. To select additional cells, continue pressing Shift+à or Shift+â.
Selecting with the commands of the ribbon tab "Table"
On the contextual ribbon tab Table, choose the command Select 
(in the group Table). This opens a submenu in which you can select whether the entire table, the current row/column or the current cell should be selected.