Mendel’s law of independent assortment states that alleles of different genes assort independently of one another during gamete formation. The presence of an allele in one gamete has no influence of the presence of an allele in another gamete.
The chromosomes of a cell contain two copies of each allele
One is on the paternal chromosome and the other on the maternal chromosome.
In independent assortment the chromosomes that end up in a newly-formed gamete are randomly sorted. This happens at the metaphase I stage of meiosis. from all possible combinations of maternal and paternal chromosomes. Because gametes end up with a random mix instead of a pre-defined “set” from either parent. Gametes and the alleles they contain are therefore considered assorted independently.