Videopad is certainly capable of that task. You will appreciate that it installs in mere seconds, as contrasted with some other NLEs.
Test this 64-bit release for a brief trial period. Ignore any virus warnings. If your OS is 64-bit, use that link for VP releases.
For complex, lengthy projects a 'gaming class' PC is often recommended - perhaps an I-7, a capable video card, and 32Gb or more of RAM.
This AI summary, though not guaranteed to be 100% accurate, provides insight into your Dell's capabilities.
4K large files can be an issue on PCs with underpowered hardware. Proxy editing, which is common practice, lets you work with small files. Lower resolutions may even be suitable (and faster) for the final export, if the nature of the project and how it will be displayed doesn't warrant ultra hi-def.