Urgent - ICT to BlueCard & Job Change

Sorry, I cannot really follow your post or understand what your situation is and what you are asking for.

i currently hold ICT visa as im deputed in germany by my indian company i have got new job offer in ulm, and the new company wants me to join in Feb 2nd week, Due to covid im not able to make an appointment at the visa office in ulm. If i don't resign my old job by this week i will not be able to join my new company as told in feb'20. Hence im not sure what to do now

Would i be advised to apply for blue card first and then resign the current job,  or can i resign my job first and then latter apply for the blue card

In case if im not able to get my blue card before my joining date, will the immigration office provide any kind of temp visa so i can start to work with the new company until it get the blue card

I have not heard about an ICT visa before, so had to google it:
Wow, it seems to be some kind of EU-wide work permit (although limited in scope, durantion and only for ontra-company transfers).
I did not know something like that existed!

But to anwer your question: No matter where and when you apply, there is no guarantee that a certain visa is approved until a given date (or at all).
Therefore it is up to you to decide which risks you take (resign before new visa is granted -> jobless in case of rejection, or resign toolate -> new employer might not want to wait).
You can also apply for a normal work permit, it does not have to be a blue card.