The green modules have a fixed focus. You will not be focusing them. The lens is glued in place...
The DPSS green modules have a very thin beam, and in my opinion, if you try to set one up for focusing, by removing the fixed lens, and using an adjustable lens, the results are not good. (IMO)
The modules come with a momentary side button to turn the laser on. Since you will be mounting the module into a host, which has it's own switch, you must bypass the side button on the module. Then the host switch becomes the 'on / off'...