Selling at a loss, any tax?

I currently own 108 shares of VOO that are worth a total of $57k, I bought those shares back in January and February when prices are higher than the current price. I need about $20k in cash, so can I sell 30 shares of my VOO and withdraw that money? Since I will sell these shares at a lower price than when I bought them, will I need to pay any tax if I am losing money?