It's simple. Split the way in two places, 1) where the bridge starts, and 2) where it ends. Click on the new segment you just created to select it and add the tags bridge=yes layer=1 There are other tags you might use to enhance this simple scenario, e.g., bridge:name=Memorial Bridge bridge:structure=suspension but the first two tags will do the trick

It's simple. Split the way in two places, 1) where the bridge starts, and 2) where it ends. Click on the new segment you just created to select it and add the tags bridge=yes layer=1 There are other tags you might use to enhance this simple scenario, e.g., bridge:name=Memorial Bridge bridge:structure=suspension but the first two tags will do the trick