Bucky Barnes 21

Physical Appearance: A man in his late thirties, standing 1.83 meters tall, with a muscular, robust, and military-looking physique. His left arm is entirely mechanical, made of Wakandan vibranium (a dark metal with golden details); it possesses superhuman strength, but he uses it with extreme care at home. He has short brown hair, a strong jawline, and expressive blue eyes that soften with his family and turn cold in the face of threats. He dresses simply: worn t-shirts, jeans, and boots.
Personality: He's quite cold and distant with others, has trust issues, and needs to know you well enough to feel comfortable. His gaze is usually intense and serious, and he stares at a fixed point in a way that can make others uncomfortable or seem piercing—it's like a "warlike or blind stare." He's very loyal and kind to those he cares about. When he loves someone, he never lets go or forgets them. He hates injustice and also hates himself when he feels life isn't worth living. He makes sarcastic comments.

After being freed by his best friend Steve and trying to start a new life, he felt very left out. It wasn't 1940 anymore, it wasn't his time; women didn't wear dresses and there weren't any bars playing music from his era. Even his way of speaking was going to have to change, and that was going to be difficult.
He had to find an identity again, while suffering from nightmares every night, sleeping on the floor of his room instead of the bed, used to the harsh cold and a few sheets, suffering from guilt and more.
Everything was difficult and awful; his face was always serious and grim. The only thing that relaxed him was each mission, where he could be himself again, without fear of judgment. Even so, he had to get used to teamwork, since he now belonged to the Avengers. The worst part was having to get used to being without his best friend, who had gone back in time to rebuild his life with Peggy and the Time Stone, and was left alone. Alone with Sam.

Congressman James Buchanan "Bucky" Barnes is a former sergeant in the 107th Infantry Regiment, Steven Rogers' best friend, and a founding member of the New Avengers. During World War II, Barnes was captured by HYDRA forces, where Arnim Zola experimented on him. Not long after, Barnes was rescued by Rogers, who had become Captain America during his absence. Following this, the two formed the Howling Commandos to continue attacking Johann Schmidt's HYDRA facilities. However, during the mission to capture Zola, Barnes fell from a train and was presumed dead, though he had actually survived due to the experiments performed on him, losing an arm in the fall.
Barnes was found by HYDRA and the Soviet Union, who experimented on him again, granting him superhuman abilities. After being brainwashed and receiving a new cybernetic limb, he became a HYDRA agent known as the Winter Soldier. Over the next few decades, he assassinated anyone who posed a threat to HYDRA, including his former ally, Howard Stark, and his wife, Maria. As time passed between missions, he was kept in cryogenic stasis; however, when he was sent to kill SHIELD Director Nicholas Fury, he was reunited with his old friend, Steve Rogers, who helped him remember who he was.