It starts where a boy has to earn money to be able to feed himself. He goes out into the forest or plain to find some herbs and that's where he saw the elf. She ask him for directions and he helps her to where she is supposed to go. In order to thanks him, she gives him a gold coin and this allowed him to buy some food from a place that he stays at. I remember him buying steak or some kind of meat saying that he miss the taste of it. The money also allowed him to buy armor and weapons to go into the dungeon. He gets help from a guide about something, when he goes inside after a while he gets ambushed by another adventurer. This adventurer plans to kill him because there isn't anyone near them but the elf from before comes out and kills the adventurer and helps the boy get out of the dungeon. This is mostly all i remember and it only had like 2 or 3 chapters. I read this about 6-9 months ago.
The manga is Kinka 1-mai de Kawaru Boukensha Seikatsu. Summary from MyAnimeList:
Istolfa - permanently poor, his primary struggles are finding food and a place to sleep at night. One day, while picking weeds in order to try and make money, he comes across a gold-ranked adventurer. The adventurer, surprised at his fortitude, gives him words of encouragement and a single gold coin.
With this single coin, Istolfa's life would permanently change.