How is processor "Shakti"by IIT Madras different from that of Intel and ARM?

As far as my knowledge goes, this is probably not the same. From what most people know, ARM is an old RISC processor. X86 is the older scaled-down version and as far as Shakti is concerned, it is a RISC-V processor which is a later version of the ARM (Acorn’s RISC Machine). It also follows the same concepts.

This probably means that if you are planning to do something new with Shakti, it would not have the outdated RISC label to it.

Talking solely about Shakti, it is mostly used as an exercise to demonstrate its ability to do design work and build processors in our country. The bar set here is quite low. They should make Silicon like the one at TSMC and that would probably have a much more lasting impact. This will possibly take some time but they will be there soon.