By following schema.org web page, I designed a single product page on a website for my client. I've followed most of the schema required to enlist a single product on a single product page.
My question is, can I mention other products on the same single product page under category anything close "You may also like"?
If so, should I add schema to those products too?
Thank you
Yes. In general: the more structured data, the better.
Schema.org defines properties for this purpose:
isRelatedTo
for a "somehow related" Product
isSimilarTo
for a "functionally similar" Product
(And for special cases, isAccessoryOrSparePartFor
and isConsumableFor
.)