Yes and no. Usually the act of inputting facts into Anki is enough to commit them to memory (as long as you’re focused on what you’re doing). But for harder facts it doesn’t always work. I have about a 40% success rate on first-time cards. Some of that other 60% is already learnt by the time it comes up for review again on the same day. The remainder are the really hard cards, which accumulate in my failed-card pile at the end of my study sessions. I spend extra time learning these, then mark them as “Difficult” so that they come up for review again in a day or so.

Specifically to Japanese studies, I find that graphemes require a good deal of extra study to learn. Kanji cards can be learnt in the time it takes to input them into Anki, as long as you remember to come up with a story while you do it. Sentences should already by learnt by the time you enter them into Anki because of the time you took to look up the words/grammar points.