A few questions

So I hope I don't sound dumb, but I have a couple questions. I've been off BC for about 5 years and we haven't ever used protection. I do not think we have anything wrong with us because we don't bd often. Now that we are ttc we are obviously going to BD as much as we can. My question is how do I know when to use a ovulation test to see if I am ovulating? Do I go by the fertile week the app gives me, then check every day or what? I started tracking my period last month, but we really want to start a family so any other tips/ideas?

I bought geritol and started using it tonight and I plan on buying pre seed instead of using ky.