In Swords of Legends Online, currently they are three life skills that are playable
Respectively they are fishing, cooking and crafting.
Each life skill can be levelled with no current level restrictions for what you can make.
The only noticeable disadvantage for lower life skill levels is the materials you gain from open world (fish/ingredients/gathering) will be untradeable. In addition, while having higher skill level will also grant you skill points that you can freely assign for various buffs.
Fish are important ingredients for cooking food. You can fish in any area with water. But useful fish product only comes from certain spots in the water area. There are two types of fish spots: blue and gold. Blue spots are personal spots while gold spots are public-shared. Blue spots refresh biweekly-weekly while gold spots refresh slightly faster. Different maps have different fish products. Each fish spot has a fixed type of fish production. You can preview the product from a spot by hovering your mouse on it. You can get extra products other than fish if you are lucky. There are super rare gears with special stat combo that only comes from fishing. There are also housing item as extra products.
There is a set of gears specifically for fishing. This gear set grants you higher abilities (more extra products, faster casting time, etc.) They can be crafted from recipes bought with fishing coins. You earn fishing coins if you fish with a special bait. There are also daily fishing task and weekly fishing events to earn more fishing coins.
Cooking is an important life skill for better battle performance. It uses ingredients you get from fishing, gathering and hunting. There are different foods and recipes for various different gameplays.
They are also different food that grant different stat boost for respective PVP and PVE content. Most recipes can be bought from general stores or reputation stores, but some recipes may only be looted from raids and dungeons. Cooking is 100% success and you may gain double products sometimes. It is also possible to get a higher quality food (higher stats) given luck. A higher skill level in cooking can grant you higher probability in these events. Skill levelling experience is usually from learning new recipes and cooking more food.