There’s plenty of free resources on the internet.
- I enjoy Imabi a lot, all the explanations are very detailed (might be too much information for a beginner though but they’re thorough): https://imabi.net/
- The award-winning Tae Kim’s Guide To Japanese is also available for free, a looooot of people recommend this: Learn Japanese – Tae Kim's Guide to Learning Japanese
- The series of textbooks Japanese from Zero also offer the first book’s content for free online at https://www.yesjapan.com/ and the author covers the other books content too for free on YouTube: https://www.youtube.com/channel/UCxuZNRnlprC70l1bnI0n-XQ (Honestly it’s a great resource, I’ve learned a lot from it, somehow it gets overlooked a lot)
- Japanese Ammo With Misa is also a good resource (https://www.japaneseammo.com/) with a YouTube channel that covers a lot of grammar topics: https://www.youtube.com/channel/UCBSyd8tXJoEJKIXfrwkPdbA
- Organic Japanese with Cure Dolly (https://www.youtube.com/channel/UCkdmU8hGK4Fg3LghTVtKltQ) is another YouTube channel that is often recommended on the forums here. If you can get past the creepy computer-generated voice it’s a very very good resource.
- The WaniKani forums!!! Lots of resources on the threads, and a whole lot of people waiting to answer your questions if you need clarification with grammar points etc. Places to start: The Ultimate Additional Japanese Resources List! or Short Grammar Questions (Part 1) if you want to see what kind of questions other users ask.
Enjoy! 