I've discussed this in the Premier League thread. The wrong injury will make Liverpool experience a bad situation in every match. Liverpool will have difficulty competing in the Champions League and will have difficulty winning the Premier League title this season. It is said that Salah suffered a hamstring injury which is an injury that takes quite a long time to recover. I don't know if this news is true or not so cmiiw. If this is true then this will make Liverpool the favorite team to win the Champions and EPL in my personal opinion.
Well, Liverpool is playing in the Europa League not Champions League.
Without Salah, Liverpool definitely will have a problem but it doesnt mean that they are not one of the favorite to win EL and PL.
Liverpool still have Diaz, Nunez, Gakpo and Jota as forwards/attackers.