Hello Kauan Henrique 🇧🇷,
Looks like you're experiencing issues with reinstalling Steam, if so, let's try this suggestion:
Delete any remaining Steam files in the following directories below depending on your OS bit. Delete the files there before attempting to reinstall Steam again:
C:\Program Files (x86)\Steam
C:\Program Files\Steam
Sometimes when you uninstall Steam, some files may remain on your computer.
Let me know how it goes.
Thanks,