Here is the item again:
If Chris hopes to survive in his 8 a.m. English class, he needs to discover
caffeine even when he has a test, his head
hits the desk by 8:05, and snores soon escape his mouth.
The blank space between caffeine and even makes a fused sentence. At this spot, there are two complete sentences joined with no punctuation, causing a major error. He needs to discover caffeine is the main clause of the first sentence. When he has a test, his head hits the desk ... begins the next complete sentence.
To fix this problem, you could put a period after caffeine and capitalize the E that begins even.