There is no “law” or “written rule” that says you cannot look at homes if you’re not already preapproved with a bank, but sheesh! You certainly owe it to yourself to do it NOW rather than wait.
Think of it as going to the store to buy something without knowing if you have any money in your wallet ahead of time. You can’t buy the groceries without the money in hand or enough money in your checking account. Buying a home is not much different than that. Why would you look at homes without knowing how much you CAN afford, or even IF a bank can or will give you a loan to buy a home?
Beyond everything else, if you do find the “wow house” and then you have to go through the approval process, now you’ve put yourself into an awkward position. And, you just could miss out on that house if someone else comes along and is already approved.
I could go on and on about the pros on getting approved first (believe me, they’re ENDLESS) but read this article and feel free to comment.