Meet Missy, my childhild grumpy cat from my grandmother whom I inherited after my gran passed last year.
She's litter trained, but shy in new spaces as she was in one space her entire life until a year ago. Patience and slowly introducing her to the rest of your house is probably the way to go.
She would do best in a single pet household. She's old, but healthy and plays sometimes still at her old age of 15+ years. She's extremely shy, which makes her growl at literally every cat or animal ever.
She's very affectionate, and was raised as a lap kitty. She's gentle, and has a habit of giving kisses once she settles in. She doesn't thrive the way she did in our home because we have other cats, whom she still hisses and swipes at a year later and plenty of thoughtful reintroductions. To be honest, I just think she deserves the peace of a quieter, softer home that will be patient and kind with her boundaries. She doesn't care to be held, but she loves laying right next to or on you.