The number of cells and the number of chromosomes at the end of each of the following stages of meio

If the haploid number is 10, then the diploid number is 20.

At the end of mitosis, a single somatic cell will have split into two identical cells.

At telophase, (prior to cytokinesis), there would be a single cell, and within it two nuclei without the cytoplasm having split yet. I am not sure the level of biology you're studying because in introduction classes, telophase is often coupled with cytokinesis, so they don't differentiate the two. Bare that in mind, please.

After Telophase I + cytokinesis, you'd have two cells having 20 chromosomes each.

After Telophase II + cytokinesis, you'd have four cells having 10 chromosomes.