A patent was a confirmation of land ownership granted to a settler after he or she had fulfilled all obligations with respect to the land—that is, the settler has cleared the land, put up a certain number of buildings, completed road work, etc. If the settler received the land as a free land grant, there would have been no patent.
Patents were not issued at the time of the grant; they were issued after the settlement agreement was complete. The process could take years to complete; do not limit your search too narrowly.
The patents are available on microfilm at the Archives of Ontario in Toronto.
Resources
Articles
From Grant to Patent: A Guide to Early Land Settlement records, ca. 1790 – ca. 1850
Research Guide, February 2015
Pathfinder to Land Patents at the Archives of Ontario
Researching Crown Land Records
Research Guide, August 2015