Thx for bringing this to our attention. We know that this system is quite confusing, and we haven't implemented any proper guiding system yet as this version is just a demo. To open inventory, you use TAB; there are quick slots at the bottom; put your items there. Then, press Q to open quick slots where you can find your items at the bottom and select them with a mouse.
Hey there! Thank you so much for the assistance. I managed to play through it but not the whole experience, the checkpoint was a bit unforgiving haha.
I liked how due to the mechanics being a bit clunky around using your inventory itens/your gun, it made for panic inducing moments where you didn't feel that much in control.
Although I do believe the inventory system can be improved (and maybe the difficulty?), the aesthetics, presentation and scare factor are all SUPERB. Wish you all the best and will play/support whatever updates/games comes next!