Change A card to F card

Hello,

I know there are many topics like this here, but I couldn't find a case like mine and now I want to ask some questions as commune isn't really helpful.

I came to Belgium in 2021 and met my boyfriend nearly 2 years ago. I am a freelancer and I have A-card which I am going to renew it in a month. We recently moved in together and want to declare our cohabitation legal and after that for me to get a F-card so I can back to university next year easier. We went to commune and they said we need to get interviewed. So now I have some questions:

What are the questions they ask? I have anxiety and I don't want to get there unprepared.

Should we wait after our 2 years anniversary to declare our cohabitation?

After cohabitation and for getting an F card will we go through other interviews?

How long does it take for changing my status from type A to type F? will it be 6 months like the newcomers or the process will be easier?

Will I get an Orange card even though I have an A card? I don't like to get that because I've heard that it resets all the years I've been here for requesting for Belgian nationality.

Thank you in advance