Is is grammatically okay to use ‘settle’ for causative purpose ? Is this sentence okay “ I settle whom I will at my home” ?
No, the verb "settle" can't be used with an object like this.
In the sense of "go and live somewhere, permanently" the verb is intransitive, with an almost obligatory prepositional phrase. "I settled in America". It would be odd to say "He settled in my home". There is a transitive sense, but it means "arrive in a new country and use the land": "People from Asia settled America over 20000 years ago" - you certainly can't use that sense with "my home".
And you can't give "settle" an object meaning the the person who settles. You can't say "I settled him in America", and certainly not "I settled him in my home" Consequently "I settle whom I will in my home" is not correct.
You can simply say "I choose who lives in my home" or if you prefer "I choose whomsoever I will to live at my home" (if you want over-the-top flowery language)