So let's say I use the Minor Illusion cantrip to create a 5ft pile of snow or rock, can my character go inside the Illusion and fire arrows from it and count as being invisible/unseen by creatures that don't have true sight/blind sight/tremorsense/ect and haven't passed a Study action to determine it's an illusion?

Quote from Nivekamras >>

So let's say I use the Minor Illusion cantrip to create a 5ft pile of snow or rock, can my character go inside the Illusion and fire arrows from it and count as being invisible/unseen by creatures that don't have true sight/blind sight/tremorsense/ect and haven't passed a Study action to determine it's an illusion?

Sure, though if anyone actually sees you go into it they'll figure out it's an illusion pretty quick.

Also, keep in mind that the illusion has to fit in a 5-foot cube. Some larger characters might not be able to hide inside something that size.

Unseen Attackers and Targets

When you make an attack roll against a target you can’t see, you have Disadvantage on the roll. This is true whether you’re guessing the target’s location or targeting a creature you can hear but not see. If the target isn’t in the location you targeted, you miss.

When a creature can’t see you, you have Advantage on attack rolls against it.

If you are hidden when you make an attack roll, you give away your location when the attack hits or misses.

It seems that, RAW, these rules would apply here.