Hello Itshussain.
Thank you for using Apple Support Communities. Sounds like you're experiencing quality issues when viewing videos you recorded with your camera. If so, we'd like to help out. If you're syncing your photos and videos with iCloud, you most likely have Optimized iPhone Storage enabled. This feature will upload full-resolution version to iCloud but keep a smaller space-saving version on your device. This might be why you're noticing a difference in quality. This resource explains more: Manage your photo and video storage - Apple Support
Your photos and videos are stored on your device in their original, high-resolution version. This means that they use a lot of space on your iPhone, iPad, and iPod touch.
You can always confirm this by going to Settings > Photos on your device. There is also an option to Download and Keep Originals to have the full resolution versions saved on your device. Keep in mind that this will take up more space on your iPhone. We hope this information is helpful. Cheers.