Can I access my photos stored in icloud on my phone on my PC?

If they are in iCloud Photos, you can log into icloud.com on a PC and see them in the Photos app there. See: Set up and use iCloud Photos - Apple Support

You can also use iCloud for Windows. See: Set up and use iCloud Photos on your Windows PC - Apple Support

If you don't have iCloud Photos turned on in an iOS device but do have an iCloud Backup, the photos would be included in the backup. You can use the backup to do a restore of an iOS device or to setup a new iOS device but you cannot view the contents at iCloud.com.