All humans have a total of 46 chromosomes, 22 autosomes from their father, & another 22 autosomes from their mother, plus a Y & X (from father & mother), making them male, or two XX chromosomes (from both parents), making them female.
Now, that we covered chromosomes, what about Haplogroups, well in this context, we are speaking from strictly paternal & maternal lines, a haplogroup is a genetic line that connects an person with common ancestors.
As for males, they will inherit a Y-chromosome haplogroup from their father & a MtDNA haplogroup from their mother, but females will only inherit the MtDNA haplogroup from their mother, which is why females when they test with a commercial Genetic Genealogy company like 23andMe, they will show that they don't have a paternal or Y-chromosome haplogroup (unless her father or full/half paternal brother or even paternal grandfather were to test, then it would show up on the results).
So in more simple words, my paternal line is my father, my paternal grandfather, his father, & so on, & my maternal line is my mother, my maternal grandmother, her mother, & so on, with my fiancee is her mother, maternal grandmother, & so on.
So, if my fiancee & I were to have a child someday, their paternal line would be I, my father, my paternal grandfather, & so on, & their maternal line would be my fiancee, her mother, her maternal grandmother, & so on, if we were to have a son, & he had a child, then his paternal line would remain the same as my son & I (my son, I, my father, my paternal grandfather, & so on), but my grandchild's maternal line will not be the same as my fiancee, as it would actually be their mother's maternal line (so my grandchild, their mother, their maternal grandmother, & so on), but if my fiancee & I were to have a daughter, & she would have a child, then my grandchild will still have the same maternal line as my fiancee, (my grandchild, their mother, my fiancee, my fiancee's mother, my fiancee's maternal grandmother, & so on), & my grandchild's paternal line will be their father's, paternal grandfather, & so on, & if that grandchild has a daughter, that maternal line will pass on to that child, & the paternal line will change once gain, being their father, their paternal grandfather, & so on.
If my sister & her boyfriend were to have a child in the future, their child (my niece or nephew) will inherit the same maternal line as my sister (being my sister, my mother, my maternal grandmother, & so on), & if they had a daughter, & my niece had a daughter, the maternal line will continue the same, but the paternal line will change, being their father, their paternal grandfather, & so on.
So, the Y-Chromosome Haplogroup (or paternal haplogroup) passes from males directly to all of their male descendants, & the MtDNA Haplogroup (or maternal haplogroup) passes from females to all of their female descendants, as well as their male sons.
So, to figure out finding out Biogeographical ancestry (race & ethnicity) & genetically-inherited Health conditions, the best way to find out is using Autosomal DNA, because you are looking at your entire lineage, not just strictly paternal or maternal lines, so by using an Autosomal DNA, I can looking at my maternal grandfather & paternal grandmother's entire lineage, of course, it would be hard to figure out what their haplogroups are, unless they wanted to test, but you can still see what you inherited from them, such as your biogeographic ancestry & genetic health conditions.
