Unfortunately no official free streams other than Free Practice 3 https://www.youtube.com/live/GWdIkY4NAFQ?si=RXFb1hrSA9cIsAZt
For those without access to the race broadcast the full races are normally placed the FIA WEC YouTube channel about a week or two after the race.
How to watch: https://www.fiawec.com/en/news/how-and-where-to-watch-the-fia-wec-action-from-spa/7961
2024 TotalEnergies 8 Hours of Spa I Full Race
https://youtu.be/tHPKqTHGzBo