@Amazoon360 the first question would be what is the original image size/quality that your images have?
As a NOTE, GoThru does not downgrade the quality of your images, and we upload the original images.
But if you upload 20MB images to Google, they will not serve 20MB per image to their users, the images are compressed to 2-3MB
But the images on Google should still look good, this is a tour shoot with DSLR in high quality and published with GoThru, and it looks very good on Google https://maps.app.goo.gl/mJY5QLaomVy1KoWE6