So since you want to learn Hiragana I assume you are completely new to the language.
I Have Genki and you don't have to buy 1 to learn Japanese. Genki Is just a start and won't even make you an Intermediate at It.
What I do to learn languages, this goes for any language, Is to just use It even tho you don' t know any vocab or grammar.
I never learned English, I just lived In an English world (PC). People that learn fast usually live In the country that uses that certain language but not everyone can just fly over just to learn a language.
so Instead of going to Japan you could use a Japanese keyboard and do the same from the Internet.
I'm not good at Japanese myself and I'm still learning but I can give you some tips I guess.
This Is how I learned so far.
1. Start learning Hiragana and Katakana, you can learn both of them over the weekend.
2. Start Learning some Kanji I'd recommend this: https://decks.memrise.com/course/141583/2136-joyo-kanji-by-grade/
You don't have to now the Pronunciations yet, that will come with time.
Just a small explanation.
There are 2 types of Reading, Kunyomi and Onyomi
Kunyomi Is the Japanese way of reading Kanji, Example: 山(Mountain) Kunyomi Is "Yama", If I say that everyone will know Its a mountain.
Onyomi Is the Chinese way of reading, So In that case 山 would be read as "San", But this Isn't as clear as the Kunyomi reading since San can also mean: Three etc. This Is to make It flow better.
There are just to many readings to just remember so thats why I would recommend NOT to learn the readings immediately
3. You can make your own course or just a list for Vocab you want to learn. This way you will also get familiar with pronunciations of Kanji
4. Learning grammar Is up to you, Genki does a good job at teaching basic grammar but apart form that you can learn much more In less time If you were using other methods.
I Personally learn grammar by reading and then making the correct version of the sentence In my own language until I don't have to think about It anymore (Like What I did with English)
I feel like I talked like I am a Japanese expert even tho I am just a beginner aswell, Most of these Tips are from how I've learned other languages and a the little Japanese knowledge I have myself.
EDIT: (IMPORTANT)
I recommend this Site, https://ichi.moe/cl/qr/?q=山本&r=htr
You can paste any sentences In there and it will show you every single word. Much more convenient then Google Translate.