As much as I’ve completed a from-absolute-beginner-to-intermediate-level textbook followed by Tobira (I’m at chapter 12/13 of 15, and I’m getting bored), much of my Japanese knowledge comes from anime. I think about a third of the grammar points in Tobira were known to me because of my first textbook, and as I went along over the course of months, most of the rest were known/deducible because of all the anime I’ve watched. I don’t use a single flashcard, because I know flashcards bore me to death. (I used to play flashcard-matching games on Quizlet to learnt French, but I dropped it after a few months as I got more comfortable.)
The problem is that to do this, you probably need a bit more kanji knowledge, and a good English-Japanese (or Japanese-Japanese) dictionary. (I recommend https://ejje.weblio.jp over Jisho.org.) Otherwise, picking things up on your own will be harder. Having a transcription is also very helpful, and you can find some for free (legally too, if I’m not wrong) on reaction blogs like Anicobin (google ‘[anime name in Japanese] [episode number in Arabic numerals]話 感想 anicobin’). (It only seems to work for anime released after 2013.)
Anyway, those are tips for if/when you want to start studying using anime and get even more out of all the anime you watch. For beginner level stuff… OK, before we drop the idea of anime entirely, you know, you can actually try studying your favourite anime songs. Not all of them are that complex. The sentences used are usually very short, and once you know basic grammar, the main challenge becomes vocabulary. I’ve picked up quite a few words and structures from songs, because now I know the lyrics. For stuff that’s really aimed at beginners, you could also try NHK Easy Japanese:
For ‘authentic’ Japanese that’s aimed at beginners, I think the podcasts suggested by everyone else sound good. I don’t listen to podcasts, so I don’t know much.
Finally (yeah, OK, I’m going back to anime…), if you have voice actors/actresses of whom you’re really a fan, or perhaps if you know of a popular Japanese media personality, you can try and see if there are subtitled interviews/events on YouTube. Sometimes (if my memory serves me), there are even Japanese subtitles. (Like, the dialogue will be transcribed on screen, sometimes with shaking or special colours for dramatic effect.) The easiest stuff to follow is usually random challenge videos or fan mail reading videos e.g. ‘Inori Minase’s (technically Minase Inori=水瀬いのり) Cute English’, in which Minase-san tries to remember the months of the year in English, so most of the Japanese used is quite simple too. There are also anime ‘radio shows’ (try searching ‘[anime name] + ラジオ/radio’) for certain series while they’re airing, and sometimes those discussions get fansubbed too, including in Japanese. I don’t know if fansubbing is common for stuff like this that doesn’t involve anime personalities, but you can try your luck. I’m pretty sure there are people who fansub V-tubers, for instance.