As you asked that you want to apply for jobs in the
CITGO

You have to apply online for jobs because CITGO doesn’t issued offline application facility

Presently there are following Job openings

Gas Station Attendant,
Maintenance Technician,
Assistant Manager,
Manager,
Associate Engineer,
Audit Intern,
Automation Intern,
Corporate Health Services Manager,
Fuel Technical Specialist,
Compliance Specialist, Information Analyst, Lab Technician,
Technical Analyst,
Lubes Financial Analyst,
Machinist, Mechanical Inspector,
Territory Sales Manager,
Corrosion Control Supervisor,
Terminal Manager

Minimum Age requirements:-

You must be at least 18 years old to apply