the meaning of deployment?

It means to put into use, without really any need to worry about context.  The context just says in what way that the things is being put into use.  You might need to send the thing to deploy it (like a payload or troops), or unpack it to deploy it (like the soft roof of a convertible or a new appliance, although no one actually "deploys" an appliance), or start it up to deploy it (like a security app on a computer), but they are all ways that indicate the thing is being put into use.

It is necessary to already have the thing available for use in order to deploy it.  You cannot deploy something if you do not already have it.

Deployment is a word, often used by the military, for sending troops into duty. ... Deployment refers to assigning people to serve in various locations, especially soldiers and other military personnel. A deployment may include soldiers, as well as equipment and generals.