Does someone have a spyware on my comp

I have an ex who is comp exquisite, and I am not. yet after he left my home my online camera was on..normally it is shut and on the bottom of my page it rea keystroke 8 something like that. Can anyone help me I don’t have a flippin clue! I have 2 children at home and I am helpless, I would at least like to know what he may be doing. Is he able to watch what I am doing and My children? I know..I know this is not Dr.Phil…Please help me. Thankyou kate