Why it is said that hadeed e chinni stone should not always be worn but only in the time of fear. What will happen if worn on regular basis? I saw it on internet. What is the benefits of wearing hadeed e chini and can wear all the time?

Internet is not the source of Islam. Ok we have books on internet related to Islam but you can’t follow shariat rule from what you see on internet. Also what we call benefits in Islam, this all goes to our amaal and action not with wearing some stone and ring. Focus on your Namaz and dua and zikr and obeyingyour parents and helping the poor. Also the most important is having the Love of Aimmah Taherin (a.s), having a solid belief in the Wilayat of Amiral Momenin Ali (a.s) and all Imams (a.s).
This stone and other thing like that has no value and will not help you on the day or Qiyamat except your deeds.