Thank you for your valuable suggestions. I am definitely going to have a look at moto g54. A friend also suggested me pixel 4a 5g and I think it supports CA. But if I can find a g54 I think it will be better than pixel and Redmi note 10 pro.I don't think A04 is capable of CA. But I also got another phone in mind and that is newly launched Motorola G54. It's official price is 50K but you should get it in 45K in market. Its above 40K of your price range but it comes with 5G dimensity 7020 hardware and 8+256 GB DDR4 and ufs 2 storage. It also has strong 4G+ support and 5G support for future proofing. You can also search OLX incase it is available in slightly used condition.
Sadly my area normal zong 4g connection is very bad, I think even CA won't make it any better. I am going to try jazz 4g tomorrow.