Look for a small set screw at the base of the handle. Remove this screw using a drill or screwdriver. Grasp the interior trim in one hand and the exterior trim in the other and try to pull them away from the door. Often, this set screw is the only thing holding the two halves of the lock in place.
Acquire a bump key. A bump key is a key that will fit the lock you want to bump, but which doesn't unlock it per se. As long as the key will fit in the lock, it can be turned into a bump key by filing every cut down to the lowest acceptable depth. 1. Bump open a tumbler lock. Bumping a lock is a quick, simple lock picking technique that is useful in the case of having to open a door that's been closed for a long time (for example, of an unused home on family property), or if you need to break into an elderly relative's house to make sure they're okay. Look for a small set screw at the base of the handle. Remove this screw using a drill or screwdriver. Grasp the interior trim in one hand and the exterior trim in the other and try to pull them away from the door. Often, this set screw is the only thing holding the two halves of the lock in place. Examine the handle and trim on the interior side of the door. Pry the trim from around the handle or lever using a flat screwdriver. Some trim may even twist off by hand. Look for screws hidden underneath. Remove these screws, then pull the two halves of the lock apart to remove them from the door. 2. Remove the trim on door handles by unscrewing it around the base of the door handle. Alternatively, if you are working with a handle-and-lock combination that doesn't unscrew but instead is latched on, pop off the trim to access the screws holding the door handle in place, using a flathead screwdriver. Remove the faceplates for a stand-alone lock cylinder without a door handle via the screws. Locate the screws on the cover plate on the interior side of the door. Loosen them to remove the plates covering the lock mechanism 1. Remove the faceplates for a stand-alone lock cylinder without a door handle via the screws. Locate the screws on the cover plate on the interior side of the door. Loosen them to remove the plates covering the lock mechanism This is showing how you can get your lock apart when you don't see any screws. This was a keyed door lever lock but I mention how to do the same with the standard handle lock. By the way I had brain surgeries that causes me to search for words so be patient.  A door knob with no exposed screws. High-end door knobs and lock sets use a unique installation style that hides mounting screws from view. When you first look at this style of door knob, it appears as if it cannot be removed from the door.  Take the door off its hinges. Use a hammer and center punch to drive out the hinge pins, if they are accessible. Once the door is no longer connected to the frame, you'll be able to slip it out of the opening and remove the lock from the interior side. Drill out the lock cylinder. Pry the trim from around the handle or lever using a flat screwdriver. Some trim may even twist off by hand. Look for screws hidden underneath. Remove these screws, then pull the two halves of the lock apart to remove them from the door. 1. Open interior doors with a hex wrench. Most interior locking doors made in the last few decades use a special type of doorknob that allows the door to be opened in the event of it being locked by accident. If your interior door handle has a small, round hole in the center, it is this type of handle. 1. Bump open a tumbler lock. Bumping a lock is a quick, simple lock picking technique that is useful in the case of having to open a door that's been closed for a long time (for example, of an unused home on family property), or if you need to break into an elderly relative's house to make sure they're okay.
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how to remove a locked door handle without the key