There's no such thing as skills in The Sims Mobile. Instead, the sims have their hobbies. There are 5 hobby stories. The first hobbies are unlocked at the 8th experience level. In time, you will earn some more. Completing hobby events also yields simoleons.
In order to change the hobby, you just need to buy new equipment and click on it. You will get a prompt - confirm the decision to change your sim's hobby.
Now Were Cooking
In order to unlock this story, you need the 8th experience level. The reward is four items, which will make it much easier to develop the hobby. After reaching level 10 of the hobby, your Sim will be a master chef.
Unlocked at level 12. Developing it, you will get 5 items. This one's pretty simple to complete, since your sim can play guitar at parties, raising interest. Party interactions can get you many points.
Tales from the Script
In order to begin the career as a writer, your sim just needs a desk. You can access that at the 15th level of experience. Your sim can develop its skills by practicing, watching TV and even taking a shower.
Yay for Vinyasas
You unlock the first yoga mat at level 17. Your sim will be able to make candles, incenses, a waterfall and a bookshelf for this hobby. After finishing the story of this hobby, your sim will become enlightened. This, however, doesn't influence its body.
Play it Again, Sim
You first need to buy the piano. You can do that only after buying the Maestro's Grand Piano Family Heirloom. You can buy it for sim tickets, which you acquire by participating in family events.