The 6 times table lists the multiples of 6: 6 × 1 = 6, 6 × 2 = 12, … 6 × 12 = 72. "6x" usually refers to this multiplication table.
"6x" can mean 6 times a variable, but most people searching it want the 6 times table: 6 × 1 = 6, 6 × 2 = 12, … 6 × 12 = 72.
Learn the multiples of 6 from 6 × 1 = 6 up to 6 × 12 = 72. Count up by 6 each time, or drill yourself with the table above.