Does it run at 24fps (cinematic) or 60fps (smooth/gaming)?
To transform a "source" file into a "proper piece," you should import it into a Non-Linear Editor (NLE):
Check the technical specs of the source to see what you’re working with: Is it 1080p, 4K, or a low-res mobile rip?
Fix exposure or add a specific "look" using DaVinci Resolve .