BLURY PHOTOS YELLOW TRIANGLE HAND EXCLAIMATION WARNING SYMBOL
It indicates the shutter speed is too slow for you to hold it by hand without something like a tripod.
Either there's not enough light in the conditions you're taking the pictures in, or you need to try changing the settings on the camera, such as increasing the ISO setting, or light sensitivity, so it can use a faster shutter speed.
If it's close range, turn on the flash.
If you can't change the settings, you can try bracing your hand against a fixed object so that the camera doesn't move, and just gently squeeze the button to take the picture. Novices frequently jab the shutter release to take pictures, which will cause blurry pictures from the camera moving.