Gumroad or Patreon  choose as per convenience 

Optimum Realism for Minecraft Java Edition and Bedrock RTX is available on Patreon and Gumroad. You can purchase the membership from any one of the sites, at your convenience.

PLaY AT  Optimumrealism.modded.fun 

The Optimum Realism Map is packed with cinematic rooms to click those mouth-watering screenshots you want to!

R4 | R5 | R6 | R6.5 |R7|R8|R9 |R10|Optimum Realism Map Click here for more versions

Optimum Realism demo versions are updated alternatively(for experimental versions) and are limited to 128x only, the  full version of Optimum Realism is updated regularly, available in 256x, 512x and 1024x HD & UHD resolutions to bring in the complete immersive experience

128x | More updated and HD resolution download

Optimum Realism is partially supported on Bedrock RTX just like the Java version, with the exception of some features. If you have an RTX™ graphics card, then you can play Optimum Realism on Bedrock RTX, or if you don't, you could download the Java version if your PC meets the minimum requirements. 

Mcpe version 

Unlike the Bedrock RTX and Java version of Optimum Realism, the MCPE version of Optimum Realism is highly experimental and has many excluded features in order to make it compatible with POM PBR on mobile phones. To run Optimum Realism with POM & PBR, you need a powerful enough Bedrock Shader and a high-end phone. You can find the instructions in the link above. If you can't download it by the link above, go here.