The usual understanding of surrender is feeling desperate, feeling helpless and giving up, and turning to a higher/superior power for resolution/help/ support/miracle. To a great extent, this understanding of surrender is true for all of us.
But one can go deeper and understand that real and total surrender are at a different level. After putting in every possible effort and failing and feeling helpless, due to any situation, circumstance or human behaviour, one has to go through the feelings of shock, disillusionment, helplessness, sorrow and acceptance of many things, such as, accepting that one is not in control of what life has in store, that nothing comes with guarantee, that one is not strong and powerful enough to overcome every setback; but most of all one then REALISES that seeking strength and bowing to a higher entity in peace, with a completely humbled heart, and a calm sort of detached disposition with being wiser of ALL human predicament, and turning to both faith and hope in some kind of divine intervention, is Surrender.
To be desperate, feel helpless, pray and plead and beg to the higher entity in the hour of sorrow or need is not actual surrender. That is mere desperation.
Actual, real surrender is total acceptance and wisdom of one's limitations and realisation that now only someone or something beyond the human realm can make a difference.
Understanding and realising the true essence of surrender truly is freeing ourself from misery, and believing that a kind, higher energy is at work, that may ease things if you let go and keep faith and hope and move inwards in peace and prayer, connecting with that higher realm of energy.