Why is my cube looking like this with the glass material? I'm new at blender and am trying to make the cube look like glass. I'm not sure how to not make it look like a mirror and have this weird texture reflection. The monkey is a better picture with what is going on. It's leaving a reflection of a forest.
No need to overcomplicate things.

Here is how you do it:

Solution 01 (physically accurate)
Use Principled BSDF shader


Leave everything as is (very important)  
Set Transmission to 1  
Set Roughness as desired
Boom, you have realistic glass.


Solution 02 (old, not physically accurate)
Use Glass BSDF


Set roughness as desired


Example of both, side by side:


Tip:
If you're going for realism, use Principled BSDF wherever you can. It solves many issues for you such as fresnel, light fall-off, etc…  

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