Use these sites to find images that are free to use, with attribution:

https://www.pics4learning.com/

https://www.photosforclass.com/

Citing Screenshot from Google Maps:

The required elements for referencing from Google Maps are:

Map publisher (Year of publication) Title of map section, Sheet number or tile, scale. Available at: DOI or URL (Accessed: date).

Example:

Google (2021). Cardiff Bay. Available at: http://maps.google.co.uk (Accessed: 5 July 2021).