@crusaders1:
I’ve read on the forum where a destroyer can block ship movements but I don’t see anything in the rules to confirm this. If I have 8 ships in a sea zone and attack a destroyer with 2 and take it out can’t I then move through that sea zone with the other 6?
Yes, in noncombat movement. A destroyer, or any other surface warship, will only block movement during a movement phase in which it exists. In your example, the destroyer exists in the Combat Move phase and therefore blocks movement in that phase. However, it is destroyed in the Conduct Combat phase, and therefore does not exist and cannot block movement in the Noncombat Move phase. If your two ships failed to eliminate the destroyer, it would still exist and block movement in the Noncombat Move phase.
It should be noted that movement blocking works a little differently in the two movement phases. In combat movement, blocking means that a sea unit may enter the sea zone containing the blocking unit in order to attack it, but must end its movement there. In noncombat movement, blocking means that a sea unit may not enter the sea zone containing the blocking unit at all. Of course, submarines are an exception.