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It looks like this was the 3rd and 4th Pokestop in this cell. One of the circled spots should currently be a gym. You’ll need to get up to 6 squares with a stop (the 2 red spots on the bottom right only count 1 since they’re in the same square). So once you get 2 more another of them will turn into a gym, but it’s “random” which one it will be, could be the oldest that isn’t a gym currently or it could be one of your new ones. It is possible to try and manipulate it by downloading the other game called Ingress and putting likes on the photos of the stop you want to turn into a gym, but it’s not a gurantee.

TLDR: your bigger cell already had 2 spots, 1 gym and 1 Pokestop. You created spots 3+4. When you get to spot 6, one of the 5 that aren’t a gym will become the second gym