The word "freer" is the comparative form of the adjective "free." It describes a state of being less constrained, liberated, or permitted to act or do without restrictions. For example, if someone feels "freer," they may feel less burdened by rules, expectations, or limitations and have more opportunities to make choices or express themselves.
The word "free" comes from the Old English word "freo," meaning "not in bondage, exempt from obligation," which has roots in Proto-Germanic and even farther back into Proto-Indo-European.