Depends on what your expectations are. If you want to play every new game at maximum detail settings, this build will probably last a year, year and half. If you are willing to go down to high or medium settings in future games, you can easily pull off 4 years, maybe more. Lower the detail settings you are fine with, the longer the build will serve you, simple as that. Also depends on the resolution and refresh rate of your monitor, if it's a 4K or 1440p 144 Hz monitor, you'll need a GPU upgrade every 1.5-2 years to keep up with the demands of games. If it's 1440p or 1080p, again it'll last longer.
The processor is an 8 core 16 thread chip, and right now almost no game goes over 12 threads as far as I know, and even those games work just fine with 8 threads, plus more than 8 cores is not yet mainstream, so until 8 cores doesn't become 'low-end', the processor will serve you well. I'd say that's at least 3 years, probably 4, maybe more. You can get an aftermarket cooler since there's budget for it, but the cooler that comes with the chip is more than capable of running the chip at stock speeds and at moderate overclocks. Someone mentioned noise - it's very subjective. Some people find that the stock cooler is silent or manageable, others say it sounds loud. I'd recommend you to try the stock cooler first, and if you think it's loud, then get an aftermarket cooler. That way you won't unnecessarily blow $70-$170 on a liquid cooler without knowing if the free option serves you well enough anyway.
No worries on the questions, better safe than sorry is always good when building PC's
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