This assumes you have enough free space on your device.
Step 1 Restore data from Samsung Cloud
Turn on your Wi-Fi.
Swipe upwards on your Home Screen to open the Main Menu.
Tap the Settings icon.
Select Accounts and Backup.
Tap Samsung Cloud.
Tap Restore Data.
Wait until all the files are successfully restored
After that install Google Photos app
Enable the "Backup and Sync" option.
Once you enabled "Backup and Sync" option your Gallery photos and videos will be synced with Google Photos. Note: this might take some time.
If you can access your photos from a device that can have a CD/DVD drive or other removable storage connected, you can then store your photos locally.