> but when using the "sBridge" function, I can't get these two "red lines" to join together, forming the
> object's handle. What would be the correct process to achieve this?
With your object like this:
If you want to make a result like this as you already have in the posted file:
You could get that by drawing in 2 lines in the side view like this:
Then select the object and run Boolean difference, using the lines as the cutting objects.
Delete these pieces:
Then select these for _sBridge:
Another way is you can select this face:
Run Transform > Rotate > Rotate Axis, click 2 points across the middle of the face for the rotation axis:
After you have placed the axis, type 45 and push Enter to rotate it by 45 degrees:
Repeat on the lower one but with negative 45 (-45) degrees.
booleano_bridge1.jpg