Create a combined system for intruder and fire alarm

I currently have a ‘visitor alert’ system consisting of :- Alexa video station Ring video doorbell (Mk 1) Ring indoor camera (Mk 1) I now want to replace my defunct wired intruder alarm and smoke/fire alarm with a combined Ring system. I need full functionality on both aspects as well as integration with my current Ring system. I think that I can achieve the visitor and intruder integration by buying a Ring Alarm pack L with siren (£XXXX ) and combining it with my existing one. Firstly, could you please confirm that this would work? Secondly, how can I add both smoke and fire/CO sensors to the resulting system and control it all through Alexa and the Ring App on my Apple iPhone 12? (I could use third party sensors if they would link) I would want to achieve alerting me both at home and when I am away for intruder or fire alerts. Can you help please?