Chromebooks use the Android version of the game, which does not have this feature. However, you can still get an image of your farm with https://upload.farm/. You can see my guide to capturing you farm here for more details: https://forums.stardewvalley.net/in...-share-your-farm-and-use-stardew-planner.152/
Although I will note I don't have info on where saves are located on a Chromebook, so if you want to share that I could add it!
Oh ok! Saves are located in Play Files->Stardew Valley->Save Files. To all Chromebook users I recommend backing them up in your drive. Opening them (the save files) and copying and pasting the files inside them into the Play Files->Stardew Valley->Save Files will get your saves back.