It should be expected that there is no way for anyone to have an infinite level of chakra reserves. Your chakra reserve's starting point is based off of your rank, and can be trained up to a max point. The starting and max point of chakra reserves for each rank is:
- Academy Student: Starting: 50 | Max: 100
- Genin/D-Rank: Starting: 100 | Max: 200
- Chuunin/C-Rank: Starting: 200 | Max: 300
- Special Jounin: Starting: 300 | Max: 400
- Jounin/B-Rank: Starting: 400 | Max: 500
- Anbu/A-Rank: Starting: 500 | Max: 700
- Kage/S-Rank: Starting: 700 | Max: 800
*Sannin and Head Ninja are equivalent to Kage and S-Rank.
Now, you must be wondering how you can train up your chakra reserves. To be precise, it is the exact same as training up your other stats. Training is your ninja meditating and concentrating the focus point of their chakra.
- AS: 150 words to reach 100 chakra reserves
- Genin/D-Rank: 275 words to reach 200 chakra reserves
- Chuunin/C-Rank: 350 words to reach 300 chakra reserves
- Special Jounin: 475 words to reach 400 chakra reserves
- Jounin/B-Rank: 550 words to reach 500 chakra reserves
- Anbu/A-Rank: 800 words to reach 700 chakra reserves
- Kage/S-Rank: 900 words to reach 800 chakra reserves
*AS is Academy Student.
Below is the chakra cost for each jutsu rank. You recovery of chakra is also detailed below, you can't just recover all of your chakra in an instant.
- E-Rank: 5
- D-Rank: 15
- C-Rank: 20
- B-Rank: 25
- A-Rank: 40
- S-Rank: 50
If you reach 10 in your chakra reserves, you are rendered unconscious and cannot fight on. But, you will still recover your chakra.
At the start of your next post, the previous one being the one where you have used up a specific amount of chakra, you will gain 5 points to your chakra pool. You gain 5 points after every post. You can't just wait a few minutes, or even days, in real life.