Talking about cats is always an interesting subject. They are unique and special, they are Cats!!!
But even if they have 7 lives they need to be protected with vaccines. Now, most people decide not to get vaccines for cats because they are indoor cats but, there is always the possibility to have unusual encounters with sick cats or sick wildlife.
For indoor cats, I would strongly recommend getting the core vaccines: PRC and Rabies
PRC: Letters describing the Feline Panleukopenia (cat flu, cat distemper), Feline Viral Rhinotracheitis (Herpes virus), and Calicivirus, This vaccine is given at 2 months old or even earlier, in the next 4 or 6 weeks would be the booster, another one in a year and then it will be good for 3 years.
Rabies: Very important vaccine. It is given at 16 weeks and it will be good for one year. After that, the second shot of the Rabies will be good for 3 years.
Non-core vaccines
Feline leukemia vaccine: It protects our kitties from an immunosuppressive disease. Given after 2 months old and a booster in 4 or 6 weeks later. This vaccine will be good for a year and then it will be good for 2 years.
I would recommend the 3 vaccines for outdoor cats because they need to have all the necessary protection to be prepared for their daily adventure. You can find more information in the following source:
https://www.canadianveterinarians.net/documents/vaccination-and-your-cat