How we can load customize maps in OSM

We are using OSM Maps in one of our application we want to load customize or Survey of Pakistan approved maps in OSM map so please guide us how we can do this.

It’ll be a two-stage process. The first is to set up some sort of server serving tiles based on OSM data, perhaps this one (though other map technologies exist and may be more appropriate for some applications).

The second is to ensure that the data that you’re loading is based on “Survey of Pakistan approved maps”. Pakistan in OSM is here, and that meets India at the line of control. You’ll want to replace OSM’s administrative boundary data with an appropriate alternative. However I’m not sure if Pakistan’s claims are fully mapped in OSM - a search finds this. Another possible source is Natural Earth.

If neither of those works I’m sure that you could manually create a relation for Pakistan in JOSM based on current OSM objects, label it appropriately, and merge it with OSM’s data. Challenges you’ll have include “how to handle map updates” since they’ll be based on the de-facto boundary, not your version of it, and how far down the admin boundary rabbit hole you’ll want to go - do areas currently administered by India have admin areas below the “country” level assigned?