I have Drug n Alcohol test on Monday morning, Can I drink beer on Friday and Sat night... I normaly drink 3 beer on fri and sat night which is extra dry platinum which contains 6.5 % in 345 ml bottel... will it affet me on Monday...

Your question is most unclear. Couldn't even approach without more and specific information, to wit: gender, weight, specific amount consumed each day, time of last drink, and type of test administered.