Lingodeer is a free app for your phone. It might be a good start.
Some friends love the website nihongoshark.com. (It's not free though.)
wanikani.com is good for learning kanji and vocabulary. It's also not free, but worth using it. It uses mnemonics to teach you kanji. You can also use then kaniwani.com to ask in the opposite direction. (Wanikani just shows you the word in kanji and you type in meaning and reading. Kaniwani shows in English and you type in in Japanese. (I can really recommend to write down kanji on paper when using Kaniwani. So you can also practice to write kanji.)
bunpro.jp is a website for grammar. But more like when you want to practice it, I would recommend start first somewhere else to get a basic understanding of grammar. It's also not free though.
In general I love learning with textbooks. I'm not sure though what I could recommend for beginner. Genki seems to be a good start maybe. Some people use Minna No Nihongo, but from what I heard it is maybe more of a book in a class setting. Here an article about beginner books
https://www.tofugu.com/japanese/beginner-japanese-textbook/ (In general Tofugu is a great website to read about Japanese language and you find many useful tips.)
I hope I could help you. Have fun learning Japanese.