Hi. Welcome to GMAT Club. You are welcome to start here: gmat-study-plan-for-gmat-novices-start-your-gmat-journey-80727.html
and take a look at the book suggestions.
P.S. The school costs are very high, so you may want to not try to save what is a 0.1% of the cost on books. But absolutely your choice and everyone's situation is different.
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