Public Transport from HKIA to Yuen Long Town Centre

I will arrive HKIA at 1pm. Are there any direct or express public transports (shuttle bus or town bus) from HKIA direct to Yuen Long Town Centre? Or please guide which is the most convenient way to get to my destination. I would highly appreciate if you could kindly guide accordingly and provide me the bus schedules. My mum aged 73 and my son aged 13 is with me. Thank you very much.