see jee main exam is a competitive exam and question pattern is mcq based, so there is really impossible to predict questions from which of the parts it will come. since p block elements are in syllabus, then question may come. however right now if it is taking too long for you to understand then you may skip it for now and proceed to next topics. however exam is delayed, so you can revise this portion later. my suggestion is donot waste too much time in only one topics.
hope you may understand.
Yes, definitely if you want to score well in JEE mains and advance then you should not leave any topic.You must read P-block from class 11 and 12 both.You don't need to do a very deep study on that but just have a glance of NCERT carefully and that will enough.
Yes they are, especially the exceptions. These are the sections from where direct questions are asked and are extremely scoring. JEE pattern is unexpected and nothing should be left out.
Feel free to ask for any further query.