To turn off Google Maps bridges go into your Google Maps and then tap on your profile icon in the upper-right.
Tap on the settings.
Scroll down and tap Navigation settings.
Go to Route Options and turn on the toggle for Avoid highways.
Google Maps does not show low bridges so if you're hauling anything tall that may not fit under a bridge you'll have to look directly at the bridges on Google Maps to see if they are a low bridge or not by looking at the height.
As of now Google Maps does not show low bridges.
However if you look on Google Street View you can see the height of the bridges that is marked on the bridge itself.
There's other GPS systems and navigation systems and apps though that do show low bridges.
But you should also be aware of the height of your vehicle and pay attention to the bridge height marked on the bridge as you approach it.
If the bridge height is not high enough then you should slow down and try to go around the bridge and not under it.
The standard height of a bridge is 16 feet.
On Interstates, the clear height of bridges and structures shall not be less than 16 feet (4.9 meters) over the entire roadway width, including the useable width of shoulder.
In urban areas, the 16-foot (4.9-meter) clearance shall apply to at least a single routing.
In some areas a bridge height may only be 11 feet depending on the age of the bridge and location.
The bridge should have the height of the bridge shown on it before you reach the bridge.
Always know the height of your vehicle that is going to need to pass under the bridge.
If you're driving an RV or pulling a travel trailer you need to know the height of the trailer or RV including the rooftop air conditioner and have the height written down and placed on your dash so you'll always know.
But most bridges are at a height high enough to allow campers, RV's and Motor homes, Travel Trailers etc and semi trailers to pass under without a problem.