Silver Gravekeeper

The MC is a really poor student that loves playing games. One of his friends is a popular student detective that convinces him into helping with a murder case. After viewing the last moments of an old man being held at gun point, the scene forces the MC into a virtual reality game, dropping him off at a desert landscape with some pyramids. The MC goes with the flow, and the first thing he sees is a BOSS sand monster and a quest option. Like any MC, he expects to defeat the Boss to win, right? No