It is not difficult to learn molds. It is recommended that you start as a fitter for 2-3 years, then study in groups and test molds for 1-2 years, and finally learn mold design.
With a total of 5-7 years of experience, the monthly salary can reach more than 8K.
No matter what kind of mold, stamping mold, injection mold, die-casting mold, it is the same. The best jobs now are in plastic molds. The low-end ones include plastic toy factories, the mid-range ones include household appliances, and the high-end ones include automobiles and medical equipment.
In short, nothing can be accomplished overnight and requires the accumulation of certain skills and knowledge. Hope this helps.