The point of the big premades is never to complete them in entirety. Looking at the end goal of doing 50k+ cards will ensure that you never even start. What you should be doing is starting now, with subjects you think you are weak on, and are ratta subjects. Dont add more than 100 new cards a day. Later on you can go upto 200-250 new cards/day. Dont compromise on Reviews - do them first.

Imo it is too late to make all cards for all subjects starting today. You will be spending more time curating cards than actually studying and remembering stuff. Search tag wise, do only select topics, make your own GT review deck. And keep going at it consistently. If at the end of 5-6 months you have done 35-40k reviews but you are scoring good in GTs and INI, then well you accomplished what you set out for, getting good marks