Its called fixing something that is broken.
fix it
fix
To fix it.
to fix or to mend
Mend
to mend
The word "repair" can function as both a noun and a verb. As a noun, it refers to the act of fixing something or the state of being fixed, such as in "The repair took several hours." As a verb, it describes the action of fixing something, as in "I need to repair my bike."
"Repair" is not an adverb; it is a verb that refers to fixing or restoring something that is damaged or broken. Adverbs typically provide information about how, when, where, or to what extent an action is performed.
mend
The prefix for "repair" is "re-," which means "again" or "back." When added to the word "pair," it forms the word "repair," which means to restore something to good condition. In linguistics, a prefix is an affix that is added to the beginning of a word to modify its meaning.
repair, fix, restore, sew, stitch, darn, patch, cobble, rehabilitate, renew, renovate
repair fix rehab remodel renovate