Yin damages Yang, and Yang damages Yin. Kidney hides a little true yang, and heart hides a little true yin. The potential of true yang rises, so the power of kidney water tends to turn over the heart fire, while the power of true yin decreases, so the heart fire decreases and the kidney fire is stored. Therefore, yin deficiency does not control true yang, turbid yin can go up and down, yang deficiency leads to fire failure and yang does not rise. Where there is true yang in the kidney, just like a real dragon, the higher the water rises, the more the dragon floats in the water, so some seemingly prosperous syndromes may also be caused by yang deficiency. Unfavorable opening and closing of kidney yang, unfavorable transportation of spleen yang, unfavorable waterway of lung yang and unfavorable urination. This is beyond dispute. Once yang deficiency damages yin, it means that kidney essence is almost consumed, and natural syndromes can be seen. And you should know that Yuan Yin and Yuanyang are hidden in the kidney, and the mutual loss of Yin and Yang damages the original elements, which is not as one-sided as you understand, so there are primary and secondary diseases.
If you have a poor foundation, I suggest reading basic theories and textbooks first. Reading ancient books at first will only get deeper and deeper.