There are some who believe they can go in deep samadhi and when they are out they claim they went into nirvana or nothingness and are happy
Yogananda warned against it. This is known as abhav yoga and the happiness felt is tamas
True samadhi / some call it maha yoga or siddha yoga / etc. is where you discover everything is in the “nothingness”. It really is not nothing. It is everything and is fully “alive”
That is what people should strive for
However to reach that status there are thousands of steps. You will not know any of the steps until you make the first step
Bhavin