Stan Lee was 91 in Avengers: Age of Ultron when he played the character 'Stan Lee'.
That was over 9 years ago in 2015.
In 2018 he died aged 95, starring in 123 films in his career, 41 of those after Avengers: Age of Ultron was first released. If he were alive today he would be 101.
In Avengers: Age of Ultron, I think Stan Lee looks: