They want me to choose one before they can present offer details. Is that normal ?
Go with whichever one interests you more. Your recruiter should have provided a detailed description of each. Offers should be the same or similar. The difference comes down to negotiation: how much will the hiring manager be willing to pad the compensation components to get you interested before saying it's enough.
Congrats on choosing azure sphere
What is Azure sphere?
Like Jeff's glass balls, but Satya's. Powered by Azure.