What is the most important word to add to a fixed mindset statement in order to turn it into a growth mindset statement?

The most important word to add is however.

Researcher Carol S. Dweck affirms that there are two kinds of mindsets:

Fixed Mindset: people think they have characteristics or qualities that are fixed and can’t change. They also consider that talent alone equals success, so they no need to effort.

Growth Mindset: people are more open and consider that through learning they can improve and grow.

"However" is the word that must be used to move from one mindset to the other because it implies the idea that there is always a better option, another choice, a possible consideration that can improve our answer, knowledge and learning process.

Carol Dweck, a researcher at Stanford University, wrote a book called “Academic Tenacity. Mindsets and Skills that Promote Long-Term Learning", where she explains both mindsets.

we don't know what poem you are referring to

explanation:

d. lennie pats too hard, and then panics.