What are the types of trees or evergreen plants?

Russian Olive Trees- grow fast, in any soil- down side is they multiply like weeds and have thorns- like the ones in Jesus' crown.  They can be be bushes or trees.  As bushes- they serve as a security hedge.  My policy is, if they poke me, they're pruned immediately.  I'd be happy to send you some "seeds" if it's legal.  Here they are called noxious weeds.  They really need control- I live in the United States, in Wyoming- high mountain desert.  We have extremes in temperature & soil.

Evergreen trees are the tropical trees where the trees get plenty of water and sunlight.  So they do not shed their leaves in winter, but all the year they shed their old leaves and simultaneously produce new leaves. Mangifera indica mango tree is one of them.

There should be junipers (cedars) and pines tolerant of growing conditions in Syria.  Cedars of Lebanon are well known for their durability and value as a lumber tree.  Check with Biology Department or Agriculture Department of your local university for recommendation of what trees to plant.  Once trees are well established, little care is needed but the young trees will need supplemental watering until they produce a good network of roots in the soil.

Although the Russian olive is a sturdy tree, they do become invasive and problematic.