Do I need to upgrade all parts to upgrade CPU?

This was a PC I built back in 2013 and still on Win7. I never really wanted to upgrade because I hated the look and feel of win10/11 but the inevitable has finally come and I need to upgrade the OS even though I would still love to keep using win7.

I have a i5-4670k CPU and I'm assuming this is too old for win10/11? I am on a really tight budget so I just want to upgrade the CPU. Would I be able to get away with just upgrading my CPU or do i need to do a complete rehaul? :(

If it does require a complete new setup is it worth the upgrade or should I just get a new budget pc/laptop?

CPU: Intel i5-4670K CPU @ 3.40GHZ (no video card)

Ram: 8GB(2x4 GB) G.SKILL F3-12800CL9D-8GBXL

Motherboard: ASUS Z87-A

HDD: WD Blue WD10EZEX 1TB 7200 RPM 64MB

Power supply: PSU CORSAIR CX600 600W

Case: Antec 900 Black Steel ATX Mid Tower