Can you get trained on the job in the oilfield?

Yes, extensively — on-the-job training is the norm for most entry-level oilfield field roles, not the exception. Drilling contractors and well-servicing companies commonly bring on roustabouts and floorhands with no prior industry experience and train them on specific equipment, procedures, and safety requirements as part of the job, under the direction of an experienced crew. That's a large part of why prior oilfield experience isn't required for most entry-level positions in the first place. Specialized or technical roles — wireline, certain equipment-operator positions — often follow a structured trainee or apprentice period at the employer before working independently. What varies by company is how formal that training is: some run structured trainee programs, others train informally on a crew. Confirm what a specific employer's training process actually looks like before assuming either extreme.