Some questions are difficult for me to answer without seeing what you’re seeing. Attaching a screen shot to your post is a great way to show me what you’re having a problem with. Here are some ways to capture what you see without downloading or buying additional software.
Whole Monitor Shot
Shift+Command+3 takes a shot of the whole monitor screen and puts the file on your desktop with a date/time stamp file name.
Shift+Command+4 gives you crosshairs to let you choose the area to capture. Hold down the left button on your mouse (or press the button on your touchpad and use another finger to drag) to draw a rectangle around what you want to photograph.
Once you let go of the mouse button, it takes the picture. Again, the file will be on your desktop with a date/time stamp file name. (If you get the crosshairs and then change your mind, you can click the Esc key before you start dragging and it will cancel the operation.)