If you ask a cultivator what they spend most of their life doing, the answer will definitely be "sitting in meditation and practicing breathing techniques".
The so-called "breathing techniques," involve exhaling turbid air and inhaling pure qi, thus continuously purifying themselves and slowly raising their cultivation realm. This is the traditional method of Daoist cultivation.
The Kunlun Cultivators, who place great importance on cultivation level, are even more outstanding in the path of sitting in meditation and Qi Refinement, with each able to stay in their cave abodes for decades without stepping outside.
But if you ask a cultivator where most of their cultivation progress comes from in their lifetime, the answer will definitely be "secret realms and fortuitous encounters."