There is a popular saying "creativity is a process not an event". Creative thinking itself can be traced as far back as possible and it has been the bedrock of most scientific principles and thus inventions.creative thinking is a process for everyone from getting different ideas over a period of time and battling with it until you finally come up with a meaningful theory.
Creative thinking requires our brains to make connections between seemingly unrelated ideas. Is this a skill that we are born with or one that we develop through practice? A study has shown that each person is born with a certain level of individual creativity, so the people who tend to agree that they aren't creative have learned the non-creative behaviour.although level of creativity range between people.
Factors that affect creative thinking
There are a lot of factors which contribute to a person's creativity which are age, gene, personal experience, etc.
Creativity can be learned as well in order to improve the level which is inbuilt in person for example positive thinking, regular writing, embracing art and nature, proper rest, sharpening your knowlege are some of the ways a person can improve there creativity.
On the final note
Creative thinking is not a one-time or a sudden thing, you have to go through series of mental barriers and internal blocks . you'll have to commit deliberately and stick with your process for a period of time until something comes out of it like so many scientists did to arrive at various inventions.
Reference: jamesclear.com