OK, so the two most important words there, are 'Internet Cafe', so the first consideration above all is price vs performance.
Keeping that in mind...my recommendations might surprise you...
* H270 motherboard...mini-ITX or micro-ATX (take your pick of either MSI, Asus, Gigabyte, or Asrock)
* Intel Core i5 7500 (not the unlocked K version...the normal locked version)
* Cooler Master Hyper 212 Evo CPU cooler (a lot better than the stock Intel one, and cheap)
* AMD RX 480 8GB, or Nvidia GTX 1060 6GB (the larger the framebuffer, the better). I recommend EVGA, Gigabyte, MSI, or Asus (in that order)
* 2 x 8GB DDR4-2400 or DDR4-3000 RAM (take your pick: Corsair, G.Skill, Crucial, Kingston)
* 500W PSU (anything more than this for this build is overkill, and a waste of money). Can't go wrong with EVGA here
* As for storage...pretty much any SSD/HDD combo will do. The Samsung EVO 850 is my personal recommendation for a Windows boot drive (m.2 version if the board supports it...price difference is almost negligible at the moment)
* Case...very subjective...for mini-ITX you have the stellar Fractal Design Define Nano S, the equally stellar Phanteks Enthoo Evolv ITX, and the Corsair Obsidian 250D.
For micro-ATX, check out the Fractal Design Define Mini C, the Phanteks P400S, or the NZXT S340. The P400S, and S340 aren't exactly micro-ATX towers, but you'll
appreciate the capability for them to support larger standard-sized ATX motherboards as well.
* 144 Hz, 1080p monitor (1440p with a GTX 1060/ RX 480 might be possible with reduced settings)
Why not anything from the AMD Ryzen platform you may ask?
Well, there's that current RAM limitation that prevents stable operation at RAM speeds above 2400 MHz, although motherboard manus are bringing
new BIOSes on-stream to address this.
There's also the unavailability of X370 and B350 AM4 motherboards, which might lead to artificially inflated prices significantly above MSRP.
Keep in mind though, as the Ryzen 3 and 5 platform matures in a few months, it's price/performance will certainly supplant anything intel will
offer in the 150-250 dollar price segment. (Well, unless Intel does some KILLER price-drops)