Can setting max dop = number of cpu's cause situation where a single query blocks other queries?

I have sql server with 8 cpus. Max worker threads setting is say 850. Max dop is say 8. And cost thread hold for parallelism is 50. This means sql server will breakdown a query going above cost threshold into 8 threads. Since each threads runs on one cpu, then does this mean no other user will be allowed to run a query until at least one of the currently running 8 threads gets released? So does setting max dop = number of cpu's cause situation where a single query blocks other queries?