how do you think it would have affected the war if Spain and Turkey had joined the Axis powers the first things that come to mind are the fall of Gibraltar ,Malta and Egypt.

I do not think that Spain would have brought much combat power to the table, but it wouls have given more ports for German subs and bases for anti-shipping aircraft. It probably would have closed the Mediterrannean and the Black Sea. The Black Sea was small supply route for the US to the USSR. It would allow the Suez Canal to be attacked from both sides. It would also have placed extra pressure on the USSR - forcing them to defend the Caucasus.