I have factor 5 lie den mutation homozygous and i want to know if i am able to fly?

Yes: with caveats. You must continue any medications you are taking to prevent blood clots. You are at increased risk of clots so you want to be in a seat that allows you to reposition your legs during flight, so economy is likely not for you. You must get up and walk every 10-15 minutes and flex your calves to get the blood flowing. It may be a good idea to tell the cabin crew your needs.