CRISPRers, how do I get KAV-1 cell receptor to identify coronavirus?

This question and the following sentence seems like a non-sequitur.

1) What does CRISPR have to do with mutating a cell receptor to bind with coronavirus?

2) Why, dear god, would you want to get a cell receptor to bind to coronavirus (wouldn't this just increase uptake of the virus into the cell)?

3) What is KAV-1 specifically? I can't find it at NCBI.

4) "I believe we can train their immune system to recognize future virus mutations." Okay?

5) What do chickens have to do with coronaviruses?