A stroke occurs when a blood clot blocks a blood vessel or artery, or when a blood vessel breaks and interrupts blood flow to an and bleeding occurs into an area of the brain. Every stroke is different.
ETA Chlorophyll works on the Liver and probably works a little. No it really doesn't, you are not a plant. Tea will oxygenate the blood. No it won't Also don't do as someone else said and drink liquid oxygen, that's really not a good idea.
Yes, blood needs to go into the lungs via the pulmonary artery so gas exchange can occur. This turns the oxygen poor blood in the pulmonary artery into oxygen rich blood which is carried back to the heart via the pulmonary vein. No, then the pathway would be wiped out and you would not be able to breathe.