What is the purpose of the journal section?
The journal section breaks your history into months, weeks and days, so you can review a period without configuring anything. Each level shows the trades of that period next to the notes you wrote for it.
You can also see every trade on one instrument over a period drawn on a single chart.
How should I fill in the journal?
A daily rhythm works best. Open the current day, write down what you did, what you observed and how you felt, then read the week back at the end of the week and record the weekly result.
At the end of the month, review the weeks and record the monthly result. Short regular entries make your review more consistent and let you recall what happened without rereading every trade.