A question I encounter often is "How much Japanese should I study before I can begin reading in Japanese?"
From my experience as a learner and reader myself and from managing a Japanese book club for other learners I can honestly say that you can start way earlier than you probably think!
There are many resources that only require knowing hiragana. Those texts usually teach vocabulary through pictures and only use basic grammar.
Some are even simpler than that: The Japan Foundation's Hiragana Books are great for those, who are still remembering hiragana characters. Every short book introduces only 1-2 new characters, so it's a great reading exercise for those who've just started.
The free graded reader 「どうぞ、どうも」 by the NPO Tagengo Tadoku only uses the words 「どうぞ」 and 「どうも」 to write an entire story. Again, this makes for a great exercise in reading hiragana and understanding context. Another "level 0" recommendation by the same NPO would definitely be 「しろい?くろい?」. This book uses the full range of hiragana characters but the grammar is simple and all used vocabulary is illustrated.
Another site with great resources for absolute beginners is Nihongo Tadoku Dōjō. If you have memorized both hiragana and katakana and know how the particles を and で work you will be able to read this text about stationary (ぶんぼうぐ) and understand everything by looking at the pictures!
The resources linked so far can all be accessed completely free on the linked websites. If you have the money to spare, please also have a look at the box 「スタート」 from the series reberubetsu nihongo tadoku raiburarī published by the NPO Tagengo Tadoku and ASK (affiliate link). This box includes 8 little books in very simple Japanese.
All these texts for absolute beginners will get you started reading in Japanese with very little knowledge of characters and vocabulary.
Reading in Japanese is a skill that requires practice. But once you get used to it, it can be such a valuable tool to reinforce new vocabulary and grammar. So please don't wait until you're "ready" before you start reading - start early at your own level!
Isui-en (依水園) is a Japanese garden located in Nara, the old capital of Japan, near Kyōto. It has been preserved since its creation in the Meiji era and is Nara’s only walking garden (kaiyu-shiki teien). Sanshutei Tea House—In the 1670s, Kiyosumi Dosei relocated this house to Isuien Garden as his secondary home.