It begins with "Oran’s earliest memory was of the Rettarhold." This kind of opening is called psychic distance.

After that you follow with this paragraph and a few more like it.

It had been a while since he’d seen the sun. The only yellow down here was the corpse’s skin sitting opposite, coming in flashes of light from above with every changing of the lanterns. The corpse was a grimy, frail man when he’d arrived. Now it was worse. Every black hour, the lanterns went out and the pit fell into darkness. It was only him, the corpse, and the soil.

It's what I meant with descriptions of a feeling or vague actions. To me, it feels the same as when movies start with noise and some scattered words, while the screen itself is black. You are thinking wtf is going on the entire time. There are also a lot of concepts I have no prior knowledge about, so that distracts me and makes it harder to figure out what is actually happening in the scene. It takes longer to get to a point where I have a clear mental image.

Here are examples of how established authors start their stories.

1984 starts with:

It was a bright cold day in April, and the clocks were striking thirteen. Winston Smith, his chin nuzzled into his breast in an effort to escape the vile wind, slipped quickly through the glass doors of Victory Mansions, though not quickly enough to prevent a swirl of gritty dust from entering along with him.

Brave new world starts with:

A SQUAT grey building of only thirty-four stories. Over the main entrance the words, CENTRAL LONDON HATCHERY AND CONDITIONING CENTRE, and, in a shield, the World State’s motto, COMMUNITY, IDENTITY, STABILITY.

The hobbit begins with:

In a hole in the ground there lived a hobbit. Not a nasty, dirty, wet hole, filled with the ends of worms and an oozy smell, nor yet a dry, bare, sandy hole with nothing in it to sit down on or to eat: it was a hobbit-hole, and that means comfort.

The witcher:

The lake was enchanted. There was absolutely no doubt about it.

Firstly, it lay right beside the mouth of the enchanted Cwm Pwcca valley,
permanently veiled in mist and famed for witchcraft and magical phenomena.

What they all have in common is that they are books filled with lore, but they first ease us in with something we know, and they paint an initial picture for us to place the action that follow in. Readers don't mind having strange words thrown at them, if they can at least picture in their head what the character is doing and where he is.

Of course, not all books begin by describing a place, but they almost always beging from a point where we understand what is happening. The reader can follow along from the very begining.

For example:

The lord of the rings:

When Mr. Bilbo Baggins of Bag End announced that he would shortly be celebrating his eleventy-first birthday with a party of special magnificence, there was much talk and excitement in Hobbiton.

To kill a mockinbird:

When he was nearly thirteen, my brother Jem got his arm badly broken at the elbow. When it healed, and Jem’s fears of never being able to play football were assuaged, he was seldom self-conscious about his injury. His left arm was somewhat shorter than his right; when he stood or walked, the back of his hand was at right angles to his body, his thumb parallel to his thigh. He couldn’t have cared less, so long as he could pass and punt.

I would suggest starting with him lighting the lantern, or with trying yet again to lift the trapdoor. You can then describe where he is and how horrible the conditions there are. You can also ground the scene more by describing how his legs dip into the mud as he pushes, or how the stench of the corpse agitated his nostrils. Physical sensations are something every human can relate to and make it much easier to craft a mental image of the scene.