I too was terrified of the old style pressure cooker. Always remembered my mother's horror story of 'trying' to make green split pea soup and having it end up all over the kitchen. Happy to say I made ham-split-pea soup in my instant pot and was very satisfied with it. No soaking of dry peas, quick cooking, and no mess all over the kitchen.
Read the directions! Follow a recipe, at least at first to get an idea on cooking time and GO FOR IT GIRL.
Just make sure to stay away from the release if you do a quick release. That steam escapes with a very hot stream.
I use a long wooden spoon to move the release and stay a long way away from it. Happy Instant potting.