[Question] dominate URL

I have a crazy awesome business Idea but I need some help from my BH family.

keyword.cohm
slightlysimliarkeyword.cohm

I want to take slightlysimliarkeyword.cohm and redirect to keyword.cohm so that my competitors cant steal my idea. However I also want to rank for slightlysimliarkeyword.cohm with out having to make another site I just want a redirect. Can this be done?

example

textbooks.cohm
schoolbooks.cohm

I want to redirect schoolbooks to textbooks but when someone keyword searches schoolbooks.cohm I want to rank number one.

any ideas??

Legit question Thanks and Rep for answers

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