You are a Fey.

Your size is Medium. While they are smaller than driders they are usually still taller than most humanoids because of their spider half.  They have the same average height and weight as a centaur. 

Your walking speed is 30 ft. You have a climbing speed of 30 ft

You can walk up most walls without issue, however you cannot walk on ceilings. 

You count as one size larger when determining your carrying capacity and the weight you can push or drag.

Additionally, any swimming that requires feet is difficult because of your arachnid legs. When swimming this way, each foot of movement costs you 5 ft. of speed.

Your teeth are venemous, you can use them to do a bite attack that does 1d4 poison damage

Your fey connection to nature gives you an intuitive connection to the natural world and the animals within it. You therefore have proficiency in one of the following skills of your choice: Animal Handling, Medicine, Nature, or Survival.

You can spin 30 ft of silk/web (rope) per short rest. You can use this silk/web to craft stuff (clothes, weapons(whole weapon if somthing like a whip or net but only parts of weapons if the weapon is supposed to be somthing like metal) actual webs to trap things, etc). Producing silk/web costs a bonus action, crafting with it takes anywhere between 1 action and 60 mins depending on the complexity of the item (simple net/whip would be 1 action, anything the dm sees as more complex than that, such as clothing, would take as long as the dm thinks it would). You can also just attack with the silk/web itself, acting as a weaker form of whip, doing 1d4 slashing dmg

They are immortal/unageing, they stop ageing after maturity (25). They can still be killed, this immortality just grants eternal lifespan and stops ageing after maturity.