During your adventure on Pokémon Sword and Shield, you will come across a Daycare. You will find it after winning the Grass Badge in Turffield, on Route 5.
Inside, you just have to talk to the trainer on the right and she will give you a Toxel.
How to make Toxel evolve?
Toxel has two different shapes. These shapes are determined only by its Nature. The other condition is that your Toxel must be level 30.
