How to change my realme 5i phones display

Sorry to say iFixit doesn't have a guide for your phone, Sreehari. However, there's a Spanish site called Nadie Me Llama Gallina that has a screen replacement guide for your phone.

Manuales / Realme 5i / Fullscreen

As is common with several Android phones, the recommended screen replacement procedure includes the frame the screen is mounted on, so the process involves gutting the phone of all components and moving them to a new screen + frame assembly. You may be able to save a minimal amount of money by purchasing a screen without the frame, but that requires an entirely different set of instructions that I don't know of a guide for. You can probably find something on YouTube, though.

Either way, you should be able to find a replacement screen fairly easily; I usually start with places like AliExpress, eBay and Amazon, depending on where you live and what's available to you.