How to use FlowBoost to compare a datetime field with ({{system.dateTime}} - 7 days) ?

I have a custom field called "Last Email Click Date" which is populated everytime a email click is triggered.

I want to do a check using FlowBoost if this date is a week ago, two weeks ago, one month ago etc so that I can do a time decay of the score accordingly.

logic is this.

Date1 = {{system.dateTime}} - 7 days

Date2 = {{system.dateTime}} - 30 days

CheckDate = {{lead.Last Email Click Date}}

if (Date1 > Check Date)

TimeDecay = -5;

elseif (Date2 > Check Date)

TimeDecay = -10;

else

TimeDecay = 0;