Fertile question

So this is my most fertile day does that seem right my past two months I haven't really watched it very much but this month I'm trying to and hopefully this will be the right month ! But was wondering if my percentage should be higher than that or is that normal ? And should we BD on just that day or the day before or day after ! Help please I want to really understand these better my periods have been irregular since I have had my very first pregnancy which was a miscarriage in October helllllppp please