Income tax on foregin dividend

In next one week I am going to UK to visit my sister-in-law for holidays. During this time I am planning to buy some shares there (from my brother's company). Before I do that I was wondering if I need to pay any India tax on that. I don’t work In India hence no ITR filled ever, however I have PAN card.

I will not bring that money in India in fact transfer it to my sister-in-law's account. I have no clue about taxes so please be gentle with your response.

thanks