If you stitch a line..... measure off an inch of the stitching and count the stitches. Many newer machines have numbers that show stitch length as 1 1/2 or 2 1/2 but how many stitches would that be? The older machines will say how many stitches it makes for a 1 inch measurement.
I use 12-15 stitches per inch for my quilting. 12 is the standard for regular sewing. When the stitches get too close together it tends to weaken the fabric...... it's like punching holes so close together that they cut a line.
Others might have different ideas about this.... This is just the way I do it. And...... just go for it. We all had to start somewhere...... you'll change how you do things as you go along..... no matter where you start.... you won't finish in the same place.