Hi Farrukh
It is possible to make certain fields on a screen mandatory for user input and you have already received responses above on how to do that. However, not letting the user skip an infotype in an infogroup would not be possible via a functional configuration. You may have to explore user exits for the same. You can consult your abap programmer for it.
However, at the same time, I would also like to make you aware of the impact when you do so. The infotypes are allowed to be skipped in an infogroup so that if at the time of hiring, the user does not have some particular information, it can be entered later and the rest of the hiring process can be completed. So when you make this mandatory just ensure that you enforce only on certain main infotypes such as 0001, 0002, 0007, 0008. Infotype 0000 is already mandatory. The remaining infotypes can be kept optional during hiring.