It is claearly written in the halacha that putting a food into/onto a dish /cup/tray/platter etc which were not toveled does NOT cause the food to be forbidden to eat.
There is a mistake among many (probably resulting from the halacha mentioned above)that one may use something one time before doing tevilah. This is not so!! If the food is ALREADY in the dish it may be eaten – no difference if the first time or any time afterward- but it is forbidden to use a dish even once before tevila.
A dish which is used generally only once and then disposed of, or something not generally used for food use, ex: cutting food with a utility knife, then no tevila is needed.
Concerning dishes not used by the original owner or things packaged for selling, there is a machlokes who is obligated to tovel it as stated above.
I was given the idea by a posek, when I want to give a dish tray etc. for a gift, I should tovel it and put a small amount of clean dry) food on it FOR MY OWN USE, and then wrap and give the gift. (This won’t work for dish(es)given in original wrappings, or for a large set of dishes which is not practical to “use” every piece).
Reminder: If one DID tovel a dish before giving away, the sender should notify the receipient that it was toveled so as not to cause a brocho levatala when it will be toveled again.
PS Glass needs tevila with a brocho, concerning china dishes there is a question in Halacha, (also different types may have different halacha), and therefore they should be toveled together with other things which need a brocho or toveled w/o saying a brocho.