Hello and welcome. Thank you for using Just Answer. Let me try and throw light on your issues one by one.
1. To begin with, If you receive a pension from a foreign country while you're living in the UK it will be subject to UK tax rules. How much tax you'll pay on overseas income depends on whether you're 'resident', 'ordinarily resident' or 'domiciled' in the UK.
Since you have received your pension in India, and since you already submit your income tax returns in India, you would have paid tax on that. So NO tax stands payable in the UK.
If you have paid foreign tax on an item of income, this tax cannot be refunded by HMRC. But if you also have to pay UK tax on the item of income and you are UK resident, you can claim a credit (foreign tax credit relief) for all or part of the foreign tax and set this against the UK tax due. You can do this by completing the foreign pages section of your tax return. The following is the HELPSHEET
The following is the Double Taxation Agrements / Arrangements with India, just for your general reference.
2.As mentioned above in Point 1, this would be taxable in UK, but you will claim relief of equivalent amount, hence tax stands avoided.
3. No, even this this will not be double taxed. You will reclaim it / avoid it in other manner. Income is NEVER double taxed. You can refer this from the link given above pertaining to avoidance of double taxation.
4. NO. This will not depend upon or get affected if you bring your money to UK from India or not. It would be just an remittance and remittance are never taxed as they are not income.
I am sure this would help.
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