Escape From Tarkov - Game is too dark and buying weapons

Hello
From what I know tehre is no chance to use ReShade in EFT. When I was played PlayerUnkownsBattleground I've never use it, it was too lame for me. But in Escape From Tarkov there is too match black points where you can't see enything even when you set your birghtness and contrast to maximum.
This is my first Question abou EfT - How to reapir it? Do I should buy something?

Second. How can I play with better weapons? From what source it's possible to buy rubles?
TY