This might sound stupid but what does genetic testing entail??

Dinah • Hi I`m dinah and I have 2 boys one who will be 5 soon another that is 9months also 1 mc.

Im only asking because I was never asked for this genetic testing with my two boys. They are going to discuss it with me at my next appointment but I would like to get an idea now that way in at least a little bit prepared at my appointment.

P.S. I had a miscarriage earlier this year if that is the reason why they are doing it.