Most acute care programs assume that you have already got acute care RN experience prior to you coming into the program. I'm about to graduate as an adult acute care NP and I'm currently doing my 2nd rotation in the ICU. I have to say, that even after 30 years of nursing, most of it in the ICU and all of it in acute care, it is still a very challenging program, and honestly I don't think it's appropriate to admit someone to the program without prior experience. Indeed, most schools, my own included, won't even consider someone without a minimum of 2 years experience.
Having been doing this myself now for some considerable time, and as someone who has a certification in critical care and 10 years ICU experience, I just don't see how someone with no experience can come into to an acute care program and glide through. There's just so much to know and so much to see. Can you walk into an ICU or critical area and glance at the monitors and machines and know instantly what's going on with them? Can you scan the long rack of IVs and understand in a second each med and what they do and scan the rates for appropriateness? Can you gather reams of information on every body system and formulate a plan quickly and safely, or know what to ask and WHO to ask when things turn bad? Even I at times can be overwhelmed with the sheer volume of information. In acute care it's less likely to come across a focused problem, and more likely to come across multiple problems over multiple systems and the need to know and understand everything simultaneously is vital.
I don't wish to criticize your choices, nor discourage you, but I live and breathe this stuff every day and I think you're setting yourself up for a very difficult situation.