Can a transvaginal ultrasound see baby clearly at 29 weeks and tell about gender also ?

Yes: usually at that stage of pregnancy, an abdominal sonogram is better, but a vaginal could still see structures. In most cases, by this stage you can determine the sex by sonogram

Yes,: a 29 week old baby will always be visualized with ultrasound. Depending on the position of the baby, however, gender determination may or may not be possible.