Sakuna: Of Rice and Ruin/Skills

Skills are divided in a few categories. There are skills related to rice cultivation, fighting skills and raiment skills.

Farming Skills
Farming skills are unlocked merely by repeating related activities. Experience is untracked and at certain thresholds a new skill will unlock.

Fighting/Raiment skills
To unlock fighting and raiment skills, rice must reach certain stats. The rice stats are converted into Sakuna's but not immediately applied to Sakuna's current status until the harvest is complete. The skills only look at the expected converted value. Here is a table explaining the process. You can see which skills you're close to obtaining by looking at the harvest report.

Fighting Skills
Frontal Smash is unlocked by default.

Raiment Skills
Round Up is unlocked by default.