How can my oldest son request a family visa for my yongest son?

Hello, my Oldest son was born in the USA and was raised for the better part of 10 years in florida, but my yongest was born in Venezuela, Im a venezuelan citizen born and raised and have no aspiration of leaving my country, but i would like all my kids to have that choice. How can my oldest kid, 11 years old now, request a visa for my youngest kid who is less than a year old. please Advise