If you need a stronger latch it will require a lot more work.
How to install a door slide bolt.
Glue this to the door where you want the bolt lining up the front edge of the plywood with the edge of the door.
Cut a piece of plywood larger than the size of the bolt.
Install and secure all 3 screws.
How much strength do you need the bolt to have.
Install the barrel bolt at a height that is easily reachable.
Mark fixings for door keep.
Level up the door bolt and then mark drill and screw the top screw hole nearest the door.
An outside sliding is a door in which the moving door is on the outside of the house whereas an inside sliding places the moving door on the inside of the house and the fixed one on the outside.
The closer it is to the center of the door the more.
Be sure that the hole is large enough to eliminate any binding of the slide bolt.
Close the door up until the keep touches the door frame.
Extend the bolt out slightly and push the bolt keep over it.
Then screw the bolt onto the plywood.
A typical placement is one or two feet above the knob but it can be lower.