Answer:
"The agenda for the evening is as follows: First, we will eat dinner; Then, we will go for a walk; Finally, we will watch a movie." (The second choice)
Step-by-step explanation:
The first choice is incorrect because there should be a semicolon in between each thing you list. This is not present the in the first choice, but it is in the second, so therefore, the second choice is the correct one.
Hope it helps! :-)