Task List/evo lv1
Pokémon evolve in different ways, the most common through being at a high enough level. You can either check out the PokéDex for the evolution requirements or find out by looking at the menu of the Pokémon. When they're ready, go to the party or the Pokémon's summary page to evolve them.
The Farm page includes a section for Pokémon that are ready to evolve.