Tests to expect from fertility specialists

So I had two miscarriages in a row. It has now been 8 months since trying. Given the recurring miscarriages I am being referred to fertility specialists who are taking too long for appointment. I am trying to figure out if the tests can be done if we manage to get pregnant or if we should wait. I am just uncertain if something wrong to keep miscarrying or if bad luck given I am 42 and risk for higher frequency of miscarriage. I am trying for my second and had a healthy pregnancy when I delivered in 2020: Anybody with experiences I would love to hear what to expect.

Thanks in advance.