hardware requirments for premier pro

Simple. You need an entire new PC system build at this point. Remember, if you need to upgrade three or more major components of a PC all at once just to even achieve mainstream budget levels of performance, then it is not worth upgrading piecemeal at all.

Specifically, you need a new CPU, a new motherboard, new RAM, a new GPU, a new power supply unit and faster disks (especially if your current system relies on an HDD that's much too slow by current standards); however, for the purposes of your particular PC, I would consider the CPU, motherboard and RAM together as one single major upgrade. The HD 5450 is, frankly speaking, an extremely lousy GPU even by the performance standards of its era. And worse, it is effectively no longer supported anymore by AMD (which bought out ATi around the time the GPU architecture behind the HD 5450 was introduced), AMD having released only a beta driver for its HD 5000 and HD 6000 series GPUs since the advent of Windows 10..

Read https://community.adobe.com/t5/video-hardware/premiere-pro-hardware-articles-to-read-before-you-buy-or-build/m-p/11557686

Moved to the Video Hardware forum.

You also need much more RAM.