What are the charaterstics of an aalim and an arif? How can one attain the position of an arif. what are the best duas and zikrs for purifying the ruh, nafs and qalb?

To become an Arif no doubt need high level of self purification. And the best way to start is to stay away from all haram and do the waajibat
Thereafter, the best Zikr to start with is the Holy Quran. Increase your love for Quran. Duas will follow later insha Allah