Tables in InDesign are "Inline Graphics" meaning that they appear in the text flow, and move as the surrounding text in the text frame gets longer or shorter.
Sometimes it's necessary to select the table as a "character", or to position the text cursor to the immediate left of the table. But it can be difficult to position the text cursor precisely between the left edge of the table and the left edge of the text frame. Here's a better way:
With the Type tool, click to the left of the first character of the text in the upper-left cell in the table. Then, when you have a flashing text cursor there, just press the left arrow key on the keyboard. This will move the cursor out of the table, and into the surrounding text, positioning it directly to the left of the table. If you then press the right arrow key on the keyboard, the cursor will skip over the table and position itself to the immediate right of the table.
This might seem obscure, but I've found it helpful on numerous occasions while working with tables. I hope you find it useful as well.