OK I am in Canada so you can price up this stuff where you are (It takes $1.5CAN to = £1Euro):
Mid Tower case (You can choose any type) I like the Fractal Focus G White/Black or Blue $120CAN (Comes with 2 fans..you might want to add a extra 120MM Fan for the rear)
Gigabyte B450M DS3H Motherboard $100CAN
Kingston 8gb 2666MHz kit HX426C16FB3K2/8 $60CAN
...if you want 16GB of memory get:
G Skill 16GB 2666MHz F4-2666C19D-32GIS $120
Western Digital SN750 Black 1TB NVMe M.w SSD $200CAN
Seasonic S12III 500 SSR-500GB3 500W 80+ Bronze Power Supply $83CAN
(If you can't get Seasonic get a Corsair CX series of similar wattage, you don't need more wattage so don't overspend)
AMD Ryzen 5 3600 $275 (Get this if you think you might 2K game down the road)
AMD Ryzen 3300X $190 (Get this if can find it....prob not tho')
AMD Ryzen 3100 $140 (Incredible CPU for way too cheap..get this for sure)
EVGA RTX 2060 Super SC Ultra $490CAN
EVGA GTX 1660 Super SC $330 (Get this if you need to trim some where)
You need a digital Win10 licence (cost is up and down like a toilet seat but you can try Amazon). You can also use a Win7/8 licence ..just type it into the product key field when you are installing Win10 (still works).
Logitech G603 gaming mouse $100CAN (new Hero sensor is great)
Cheapo Microsoft 600 wired keyboard $20CAN
Sound? Speakers? Headphones? Do you need wireless? Do you want a UPS to protect it all? Do you need a optical drive for DvD/CD?
This should all be in budget depending on distribution there.
Let me know! =)