Affiliate Marketing Secrets

I have started writing this story which goes like this so far:
“Tait lay in his broken bed. The large shed that he had been living in had a wrecked roof and the door had almost been ripped off its hinges. He walked over to the the corner of the room and pulled out a half eaten loaf of bread. He tore a piece of it off and shoved it into his mouth. He looked out of the grubby window and gave a little smirk. Today was Saturday and all boys in London who were like Tait knew that this was a good day. He quickly put on some clothes (not that he had many) and ran outside. He walked down the road to the big courtyard. He looked at the market with a grin on his face. “So I need bread, a bit of meat and something which can get sell to get a lot of money,” he whispered to himself. He slowly walked from stool to stool looking at everything that they sold. One by one things from stools went missing and Tait’s pockets became full of things.
“Gotcha!” a man said grabbing Tait’s wrists. Tait turned around only to see a middle aged man with a light stubble on his face. “What have you taken today?” the man shouted.
“Nothing, police officer, I have taken nothing!” he cried back pull the policeman’s hand off of his wrist. He walked off at a steady pace but once he realized the police officer was following him he made a dash for it.”
I want Tait to go on some adventure or something like that but I am not to sure how to do that, HELP!
P.S. What do you think of it so far?

ACROSS:
7. study of the development of organisms that shows common ancestry, such as limb buds on a snake (10 letters)
14. type of evolution that involves a symbiotic relationship involving two unrelated species that depend on one another (11 letters)
16. structure similar characteristics due to common ancestry, such as bones in the limbs of tetrapods (10 letters)
19. structures that no longer have a function but are reduced forms, such as human appendix (9 letters)
20. type of evolution when two distantly related species develop similar characteristics, often because they have similar niches (10 letters)
21. theory that evolution occurs at a slow and steady pace (10 words)
DOWN
2. the process by which isolated populations of the same populations develop different characteristics (10 letters)
3. goosebumps are an example of this type of adaption (13 letters)
5. process by which those characteristics that permit survival and reproduction are continued and eventually replace less advantageous characteristics. ( 16 letters)
6. population numbers become very low then rebound, resulting in a change in allelic frequency. ( 10 letters)
9. process of dispersal, adaption, and subsequent speciation (17 letters).
15. random and permanent change in the DNA of an organism (8 letters)