Where does it says drink but don't get drunk in the old testament?

I hope this helps.

No longer drink water exclusively, but use a little wine for the sake of your stomach and your frequent ailments. 1 Timothy 5:23 NAS

Give strong drink to him who is perishing, And wine to him whose life is bitter.

Provers 31:6 NAS

"Intemperance was common enough, and The Bible contains a number of unfavorable references to excessive drinking. Wine is praised; it rejoices God and men (Judges 9:13); it gladdens the heart of men (Psalms 104:15); it gladdens life (Exodus 10:19); it makes the heart exult (Zechariah 10:7); it cheers the spirits of the depressed (Proverbs 31:6) . . . The attitude of Jesus toward wine, like that of the entire Bible, is neutral, praising its use and finding fault in its intemperate use. Certainly the production of wine at Cana (John 2:1-11) scarcely supports any belief that Jesus or the primitive Church regarded the use of wine as sinful in itself." (Dictionary of the Bible, John L. McKenzie, S.J., Bruce Publishing Co., 1965 ).