This verse sets the scene for the story of Bartimaeus' healing by Jesus. Here's a breakdown of what it means:

"They came to Jericho." This establishes the location of the event. Jericho was an important city in Judea. Jesus and his followers were traveling to Jerusalem, and Jericho was on their way.
"As he went out from Jericho, with his disciples and a great multitude..." This indicates that Jesus was leaving Jericho, not entering. He was traveling with his disciples and a large crowd of people. This is important because a large crowd often accompanied Jesus, signifying his growing popularity and the belief that he could perform miracles.
"...the son of Timaeus, Bartimaeus, a blind beggar, was sitting by the road." This introduces Bartimaeus, the key figure in the upcoming story.
"the son of Timaeus, Bartimaeus..." This emphasizes Bartimaeus's identity. Mark specifies his name (Bartimaeus means "son of Timaeus") and provides his father's name, likely because he was a well-known figure in the community, despite his blindness. Giving his name also lends authenticity to the story.
"...a blind beggar..." This highlights Bartimaeus's physical condition and his social standing. Being blind meant he was unable to work and forced to rely on begging for survival. He was likely a marginalized and vulnerable member of society.
"...was sitting by the road." This indicates his position and his purpose. He was sitting by the road because that's where he could best attract the attention of passersby and ask for alms. His position also symbolically suggests his spiritual state: he is on the periphery, on the outside looking in, longing for help.

In essence, this verse is a simple introduction, but it sets the stage for a powerful story about faith, healing, and inclusion. It presents a contrast: Jesus, surrounded by a large following, contrasted with Bartimaeus, a blind, marginalized beggar. The verse sets up the anticipation of their encounter and the potential for Bartimaeus' life to be transformed.