Being bilingual can help to develop some abilities like, motivation and attention, these skills are important to understand easily many things easily and assist studies.
... you should have stopped the first sentence after "motivation and attention". Then begun the next line.
When student starts learning a new language,it is necessary to learn grammar rules
Well, overall I feel your contents lack logical reasoning. You keep telling various reasons that benefit an individual when he learns a second language. But reader cannot grasp them convincingly as they do not have a proper base. Either you should have given examples to support your reasoning or you should have given more conceivable reasons like;
1. Learning a second language enhances one's communication ability
2. It also helps a person to enhance his or her outlook and there by broaden his/her perspectives.
3. A second language helps people with career opportunities - they standout others in competition.