I do have flat on ground floor in my apartment; I need help with respective of water outlets; We do have good water moment in our apartment; there is no water sealing, leakage or else; but I am facing problem regarding inserts and reptiles entering through those outlet; i.e. from bathroom water outlet; kitchen water outlet; toilets; which is more dangerous; I am also worried about access water, like in case of heave rain or flood; water can re-route inside my house; and in that condition insects and reptiles will enter my apartment.

I need help to know any water outlet system which is one way; so it will restrict all these problem.

What kind of "water outlets" are you talking about ? Sewer pipes ? Water pipes ? Holes in the wall around pipes where pipes enter your bathroom/kitchen ? Please, be more specific.. Thank You

Where pipes enter into bathroom/kitchen.

Those penetrations should be sealed with escutcheon installed over the pipe covering any possible opening. You can also caulk around the pipe before you install escutcheons. If the holes are bigger, than cover them with Fix-All or similar patching mixture.

How big are those holes ?

If I were faced with this problem as a tenet I would want the cheapest and fastest way to seal off those openings. I would purchase a can of expanding foam and fill all those cracks, crevasses and openings that allow those nasty critters entrance to my home. Good luck, Tom