np,
IF("Task Name]="Design" and [Duration] > Days(2), "FFAEB9") // pink
That formula above assumes that the field type for the duration is a duration field type. If it is numeric field type representing the number of days, then the formula would be
IF([Task name]="Design" and [Duration] > 2, "FFAEB9") // pink
You can use "red' for the color, but its such a dark red that you can barely
read the words. Laura ( another fine QSP) has a great tool to select colours here
https://laurahillier.quickbase.com/db/bhy8pumuk?a=q&qid=1 you just put in the hex code for the color. I like to comment the color as who remembers that those codes mean when you go back later to edit it!!
The // at the start or anywhere in a formula line means that it's a comment and Quick Base will ignore for Syntax checking
Then if you have multiple criteria it would look like this
IF(
[Task name]="Design" and [Duration] > 2, "FFAEB9", // pink
[Task name]="Install" and [Duration] > 10, "FFAEB9", // pink
[Task name]="Invoice" and [Duration] > 1, "FFAEB9") // pink