The sounds U [U] and OU [oo] are not only hard to pronounce, they’re also really hard to distinguish for English speakers ! Let’s work on it !
1) The sound U
To pronounce the sound [U], hold your tongue as if to make the [ee] sound, and round your lips as if to make the [oh] sound -> [U]
Examples :
Salut ! (Hey!)
Tu (You sing.)
Culture (culture)
2) The sound OU [oo]
ou (or) / où (where)
sous (under)
Tout (everything)
3) U [U] vs OU [oo]
rue (street) roue (wheel)
rugir (to roar) rougir (to blush)
tu (you sing.) tout (everything)
je vous ai vu (I saw you)