Hello,
I have gone through your project description and i would like to help you execute it.
For google photos, you select to add/insert a file like a normal file. The pop up menu has several options, add either a folder, a scan,upload, google docs, google sheets or goggle slide. Select upload. From there it should redirect back to images or generally, storage. Select the file you want.
Once you have done that, it should upload directly if you have good internet connection.
However, if your must not be more than 2MB in size, otherwise if it is bigger, it will not load. This is standard google standards and there are no exceptions. To check the image size, click on the image properties and check on the size description. The image should also be either in .gif or .jpg or .png. You can also check your image type from the properties.
i hope this will help you out.
Looking forward to your response.
Kind regards,
Monica Mutinda.