No. Free legal downloads do not exist for this show. However, many libraries offer DVD/Blu-ray rentals, and you can rip those for personal use (legal gray area depending on region).
A quick Google search for the keyword will flood results with sites like Pirate Bay, 1337x, RARBG (defunct but clones exist), and YTS. Here’s why you should avoid them: spartacus blood and sand web series download
The most straightforward and legal way to watch "Spartacus: Blood and Sand" is through official platforms. Although the series originally aired from 2010 to 2011 on Starz, you might find it available on: many libraries offer DVD/Blu-ray rentals
For Apple ecosystem users:
If you prefer to own or rent individual episodes or seasons: RARBG (defunct but clones exist)