All insecurities, doubts, crisis and dreads are cured through Our Lord Jesus Christ.

>what's our purpose?
To follow God's laws and live as He intended.

>is there meaning of life?
Yes, but it is too hard to grasp it, don't even try, trust that God will bring everything that is hidden to light and judge everyone perfectly. That is not to say you shouldn't try to acquire knowledge about the world, you should, but don't expect some sort of transcendence, third eye opening experience or something, don't expect to reach higher levels of understanding. All doctors, experts and intellectuals are just as clueless as you, the difference is that they memorized more information than you.

>why insist in this life if death is inevitable?
Life doesn't end in the grave, if you trust our Lord and love him you will live forever in Heaven.