A tear in car upholstery is not always easy to repair, but with time and patience, most people can repair small holes without having to pay for expensive materials and tools. You can take your car to an upholsterer to be repaired, but they tend to be expensive and often end up recovering the whole seat. Frequently they cannot match the original fabric, so you end up with seats that do not match and a big bill.
It is easier to repair fabric seats, than vinyl seats. All you need is a strong needle and good thread, both of which you can buy from your local arts and craft shop. Match the colour of the thread to your car seat carefully a good match is key to getting a reasonable result. Make sure that the needle you buy can cope with thick fabric, but has a small enough eye to pass through the fabric without leaving holes. Check that the thread can pass through the eye too. Upholstery thread is thicker than sewing thread.