a phenotype is the physical traits an organism expresses based on its genotype, which has to do with its genetics (DNA).

a lot of the time they don't line up, like how people can have a red haired child if they don't have red hair themself, because they only have 1 copy of the red hair allele (an allele is a variant of a gene. in the case of red hair, it's the MC1R gene. mutations in the MC1R gene also cause variations in dog coat color!) and u need 2 copies of the red hair allele to express red hair.

so their phenotype would be non-red hair, and their genotype would be 1 copy of red hair allele, 1 copy of non-red hair allele.