Even though UX and product design are technically two different roles, in practice there’s often little difference between them — and the exact tasks vary from company to company.
What a product designer does
A product designer is involved from start to finish: understanding the problem through UX research, exploring solutions with wireframes and a prototype, designing the final UI, and validating it through testing. Along the way they work closely with product managers and engineers to ship something that is both usable and viable for the business.
Product designer vs UX designer
The two roles overlap heavily. The difference is usually one of scope: product designers tend to own the whole experience and tie their work directly to product and business outcomes, whereas a UX designer may focus more narrowly on research and interaction. Always read the job description — titles are used loosely across the industry.