Pimples can contain pus= yellowish liquid. This pus contains dead white cells and bacteria. If there is still liquid in this pustule/pimple you can try to drain it. (https://www.mdacne.com/article/how-to-safely-pop-a-pimple-without-the-risk-of-scarring). After it drained you can cover it with a drying lotion or a pimple absorbing patch. (Check the tips section of your personal routine for specific products).