Liverpool is an extremely well coached team that also relies on certain individuals or some combination* of players.
At full strength, it will take two excellent games from us capitalizing any mistake they make, assuming they aren't performing at their absolute best either.
It is doable but it comes at a bad time (Milan and Napoli away games just before), there's probably some Coppa game in between, too.
*Liverpool relies a lot on Salah obviously, and/or the combination of their attacking trio [with any of Salah, Firmino, Mane, Jota]. If they only have two of these guys, they probably won't trouble us. Then there's Alexander-Arnold who can be a catalyst with his set pieces and crosses. Defensively they aren't that good, but that's because of Alisson [not in peak condition anymore] and Van Dijk's influence.
I'm not wishing for them to be injured or whatever, but there can be an argument here that their side is not very deep, like City for example. They need everyone at top condition to sustain their great level and it's not a guarantee. Unfortunately, the same can be said for us. Especially at the back. Without our starting trio, we cannot achieve much here. Having no Barella will be a problem as well. Losing Brozovic for the tie for example will definitely ruin any chances we have.
Essentially, we can assume that we're outsiders, but when the fixture comes closer we can see what our real odds are based on who will be available from both sides.