Welcome! If you get stuck on something, don't hesitate to ask, or for that matter find out yourself on the wiki. Just remember that there's no real rush to do anything (apart from various forms of requests that have a time limit, and there's no penalty for failing those). The seasons will come again, the requests will show up again if you run out of time. And for those that don't have a time limit, they'll wait for you until you hand over the requested item.
Most choices in the game can be made anew (apart from what to do with the cave on your farm) with some time and/or G. Picked the wrong spouse? You can file for divorce, but it will cost you. Picked the wrong profession for a skill? You will come across a way to remake that choice, for a cost.