There are a number of channels in Youtube specially catering to the aspirants for different government exams and the subjects it covers, in order to simplify the preparation process. You can go through all such channels such as Unacademy, StudyIq, Oliveboard,Adda247, Mahendra Guru, GradeUp, Testbook etc.
You may watch a few videos, and can select accordingly which educator's way of teaching seems easier for you to understand the concepts, and follow it accordingly.
However, after learning the concepts, practise is the key when it comes to performing better in Aptitude.
Hope, this helps.