Hi @Mo_Chi
The Chancenaufenthaltsrecht is only for people with a Duldung. You fulfil one of the main requirements, as you had been in Germany with a residence permit for 5 years on the date of October 31st 2022. The requirement to have a Duldung can in some cases be difficult if the Ausländerbehörde does not issue a person with a Duldung but instead other types of temporary papers. In German these are often called ‘Bescheinigung’, such as one type called a ‘Grenzübertrittsbescheinigung’.
If there are at present no other viable options for you to get a residence permit (e.g. for work or family reasons), then I recommend you request a Duldung. You have to provide a reason to be given a Duldung. Based on what you have written, your medical condition could be such a reason. However, the authorities need to have it confirmed by your doctor that you are unable to travel. There are other possible reasons to be issued with a Duldung, such as not having a passport or there being no travel connection with your home country. If you are refused a Duldung, then I recommend you get legal advice on appealing the decision.
This is a good guide to the Chancenaufenthaötsrecht:
https://handbookgermany.de/en/chancen-aufenthaltsrecht
Other options would be the residence permit 25b if you are able to work enough to cover some (but not all) of your living costs and speak German at A2 level. As you have a university degree, if you find qualified work then you can get the permit 18b. There is also the permit 25,5 for a person who has a Duldung for 18 months and where the reason for the Duldung is unlikely to change.
Best,
Éanna