He is mentioned in the Torah and Gospel just not directly by name. But he is there. You just have to know the correct maning of the relevant passages. The Book of Revelation in particular in the NT contains a few references. The Beast and the multi-headed dragon and 666 all that are representations of Muhammad's betrayers.

you don't seem to know much about religion but the things you see on TV

Pretty easy to forge. I'm sure it wont be overlooked for long and the problem will be rectified like its been there since creation.

Understanding the philosophy behind existence and  life through Quran, perhaps?

The purpose of life is not ultimate justice or or god being the most merciful, that is the conclusion of all things.

As for the reality of the world, "created death and life to test you [as to] which of you is best in deed" it was never meant to be perfect. Not from Quran perspective anyways.

I had no reason to believe that false book anyways (the Qu'ran). Christ came, he saw, he loved, and he conquered (that is, death). He and His love are all any of us need.

Regarding Torah/Gospel quotation, please check the video. There is tons of quotation taken from old and New testament showing Muhammad in the bibles, and not what church intepreting (against the bible text). Take your time to understand. I hope this thread is about educating and understanding and not "flaming" and spread the hatred.

Here is my anwer for your other questions:
1) Christian Jesus is not Muslim Dajjal. We believe when the Jesus (Isa) will return to earth (2nd coming), Muslim and Christian can idendify him as Jesus. He will correct misconception of Christian that he is god. Devoted Christian will later join Muslim to fight with Dajjal. Jesus is the reason for the unity between Christian and Muslim and with both combine, they will strong enough to fight Dajjal (which is failed to be defeated by Mahdi). So, the answer is.. Christian is not Dajjal.
2) I'll not comment on Mahdi as Christian AntiChrist from christian perspective... but in muslim perspective, Mahdi is the best imaam (leader). When muslim is strong but in chaos due to not having a true leader, they are attacked by Gog and Magog. Mahdi reluctant to be a leader but later forced to take the leadership from muslim. Syiah and Sunni muslim both recognized this is Mahdi. Mahdi is the reason of Sunni and Syiah unified and together, they are strong enough to defeat Gog and Magog. However, they are not strong enough to defeat Dajjal. Then Jesus come (read my answer (1))
3) Bismillah didnt have any 666/chi. Not sure where u get that. Perhaps from some conspiracy website? . Bismillah is  the glorification of Allah. The meaning is "In the name of God, the Most Gracious, the Most Merciful". We read bismillah everytime before we start to do any work, eat, drink, talk etc. Everything what we did we hope for Allah pleased (Redha)

this thread going tooo fast. After i finish answer 1 question, there will be 5-6 question. There is no way i I can catch-up anymore. I not sure what to answer next (and will be 5-6 additional question/false statement after that)

I don't understand. Allah says he/she is the most merciful period but he rarely shows it. Can you show me his mercy? I am not asking about the purpose of life or how it should be. Edit: I am not sure what you are trying to tell me to be honest.

If i'm correct, Dajjal in islam mean "Anti-Christ" from christian perspective. I see some christian website relate between this both.

Are you even aware that they (Moslems) believe that the Bible (Torah and Gospels) were tempered with and changed with subtractions and additions? Also are you aware the Torah and Gospels today are not the original ones (which were likely revealed in Aramaic). So Quran is talking about the original texts, not the Bible of the present!

Have a little respect, man, before jumping to conclusions...