I am a technical secondary school student, now facing an internship and employment, I am very confused about the prospects of molds. I heard from the teacher (a teacher who has worked in the factory for more than 20 years) this line must be spent in the workshop for three or four years to be familiar with materials When doing design, what if I study design by myself in the later stage, but may not be familiar with the materials? 

Do I have to stay in the workshop for several years to have a certain foundation? 

Do you have any good suggestions or comments?