Can I transfer my photos from my iphone to my chromebook?

If the Photos are in iCloud use https://support.apple.com/en-us/HT204264 to help with downloading photos from iCloud.com to the Chromebook.

If not, the option to import via a physical connection from phone to Chromebook is at least not something that is supported by Apple (Import photos w/ Chromebook isn't in https://support.apple.com/en-us/HT201302). In that case I'd contact Google Store support and see if they have any options.