This £116 motherboard supports the Core i9 13900K and cheap DDR4 RAM
One mistake I often see novice PC builders making is overspending on the motherboard. It's true that higher-end models offer more features and can support better overclocking performance, but for the vast majority of people you're better off putting your budget towards the highest-tier graphics card and processor you can afford - as these actually determine in-game performance! - then slotting in the cheapest motherboard that gets decent reviews and supports your components.
One excellent example of just such a motherboard is the Gigabyte B760M Gaming X DDR4, a simple option that supports 12th/13th-gen Intel processors all the way up to the 13900K. With an asking price of just £116 right now, you can pick up this plus a cheap 16GB DDR4 RAM kit for just £152, letting you spend the vast majority of your PC budget where it really matters.