Believing that your talents can grow and be developed over time, that you are not a static entity, that you can grow, is the basis of a growth mindset. Someone with a growth mindset feels that they can improve, or become more capable with intentional work. Someone with a fixed mindset would feel that the lot they've been dealt is what they have to work with and they can't necessarily improve.
When working to help others to develope a growth mindset, it is important to help those people see how a growth mindset is seein in others. Like anything, we can have a growth mindset in some areas and a rather more fixed mindset in others. It isn't always an either / or, but rather understanding the continuum.
Who do you know that has a growth mindset?
Who do you know that has a fixed mindset?
How do they each talk / act?
Do they have sensetivities around being wrong?
Are you one way or the other?
With a growth mindeset we can see each place where we've made a mistake, haven't been chosen for a job, or other challenge / hardship as a learning opportunitiy. With a growth mindset, we work to unpack the causes of this particular setback and treat them as a learning experience. With a well developed growth mindset you can start to find joy in being wrong, as it gives you the fuel for developing a new perspecitve on a particular topic.