You will need to access the camera’s memory card to delete photos. First, remove the memory card from the camera and insert it into a card reader. You can then connect the card reader to your computer and access the memory card’s files. Select the photos you wish to delete and delete them like you would any other file on your computer.
Alternatively, you can delete the photos directly from the camera’s display if the camera has that feature. With wireless trail cams, you may be able to delete photos remotely. Cameras which send data to cloud servers will typically auto-delete old photos from a local SD card. In addition, most trail cams will automatically delete oldest photos once the memory card is full to make room for new ones.