Bobbon thread is too losse /thread breaks no

Clean out the bobbin area.

Thread the machine with the presser foot up. This opens the tension so the thread can enter. Threading with the foot down closes the tension and the thread cannot enter as it should. When you sew, the top thread is loose and cannot properly connect with the bobbin thread to form a tight stitch. The stitching does not hold and pulls right out.

Thread breakage - top thread? Check the thread spool to be sure there aren't any nicks to catch the thread.

When the thread breaks, check the spool pin to see if the thread is unwinding too fast and wrapping around the pin. Thread nets can help stop this. You can find them at sewing machine dealers.