Choosing a topic to write about is the first part of the writing process. You might chose an experience or person that had a lasting effect on your life.
Select a comfortable place with the fewest distractions. My favorite place is in the garden. Whether I am planting seeds or pulling weeds, I feel a certain tranquillity while gardening. There are always plenty of weeds to pull to keep me there.
It is important to have a voice activated recorder to remember the gems. I use a smartphone with Google Assistant App to record. Using an earbud to access the phone features keeps the phone clean.