The point is to find keywords that enough people are searching for, but not so competitive that they are impossible to rank for.

Best keyword research tools that I use are:

1.Ahrefs

2. Keyword planner (free)

3. AnswerThePublic (free)

4. KWfinder (free)

5. UberSuggest (free)

6. Google Autosuggest (free)

7. FaqFox (free)

Good luck!