I would like to know about importance of istekhara that in what condition one can opt for istekhara? And can we do it by self? or better to get it done from scholar or a person who is very consistent in ibadat? And what is the authentic method for doing istekhara?

It’s very useful when one is in doubt and needs directions however it should not be abused and one should use their intellect and consult with other believers. One can do it themselves however it’s better to ask someone who is able to interpret the holy Quran if it’s done with the holy Quran which is the better option