In short, yes. You can back out of the offer, but the consequences you’ll face (if any) will depend on how far along in the process you are and whether there are contingencies in place. Until the purchase agreement is signed (read: legally binding), the buyer and seller can back out of the offer.
In terms of consequences, you might lose your earnest money deposit, which would compensate the seller for taking their property off the market. And you’d risk being sued for breach of contract once you’re past the negotiation stage.