This is lovely. You could contact the priest and introduce yourself, say what you said here, if you like. He will invite you to attend mass. You can just go along if you want.
Call ahead and check if you can turn up or if you need to register. Bring a face mask.
Don't worry about not knowing what to do. It's all changed because of Covid. There's a real mix of people following the usual order of standing up and kneeling etc, and others just sat tight.
Your mask will hide whether or not you know the words so no reason to feel self conscious.
My church has been open throughout the pandemic. I know others are still shut.
When everyone goes up for communion go for a blessing. Fold or cross your hands rather than cupping them for a wafer (host). Then the priest or celebrant will hold up the host and say "may the Lord bless you and keep you" or similar. Then go back to your seat and kneel or sit to pray for a little or longer time. A blessing is especially nice and powerful if you are looking for guidance about faith. You can ask God to help you and guide you in your search for faith.
Catholics keep themselves to themselves a lot so you can be private if you like.
I think you might find mass a bit hard going at first. Just let it wash over you and dont worry!
Any questions ask here. Mumsnet is really helpful for chatting to others in a faith. You just have to ignore people who think its OK to insult the faith.