We don't know exactly what Jesus looked like, because no paintings were made of Jesus during His lifetime. Any portraits you see today come only from the artist's imagination–although some may give a vivid impression of His character.
Any painting that suggests Jesus was weak or unmanly certainly misses the mark. Jesus clearly had great physical stamina; without it He could never have kept up the intense pace of His ministry. He grew up working as a carpenter–a physically demanding job. He also forcefully expelled from the Temple in Jerusalem men who were making money from the worshipers–an act of great courage and strength (see John 2:13-16).
The important thing isn't what Jesus looked like, but who He was and what He did. The Bible calls Him the Son of God, and tells us that He was not only a man but also God in human flesh. It tells us also that He lived a sinless life, and He went about doing good. Most of all, it says that He came to earth to save us from our sins. He did this by dying on the cross for us.
Do you know Christ? Have you ever committed your life to Him and asked Him to come into your life? The Bible says, "To all who received him, to those who believed in his name, he gave the right to become children of God" (John 1:12). Give your life to Him today.