My coworker and I are being given my boss's business I don't think we'll be able to run the business together without conflict what are some options

If you anticipate conflict, then your best option is that one buys the other out of the business.  This generally requires a valuation of the business which sets the purchase price, a payout of that price over time, a non-competition agreement for the person being bought out so that he does not compete against the business and take its customers.  The sales transaction must be supported by a written contract because oral understandings really don't do well in court in the case of a dispute. Another alternative would be a written partnership agreement defining each of your rights and obligations but that assumes that you two can work together   Jay Levy