Narrow Path,
That's a very honorable question that I trust that the Lord will help you with.
Normally, I encourage Christians to start with the gospel of John. However, it was just last week that I reconsidered this very question. The interesting thing is that you just asked it and I had no idea that it might be of use to someone this soon. My new thought on this and advice is going to help you to accomplish your goal.
You have a desire that pleases God, so ask Him for help each day. I think He will answer your prayer.
Please start by reading the book of Proverbs.
Here are two online copies that you can see which is more legible for your eyes. If you have a paper KjV with large print, that is preferable, but not required by any means. Just keep in mind that I don't recommend the bright computer screen or phone just before bedtime.
Please bookmark for ease of daily use.
https://thekingjamesversionbible.com
AND
https://www.kingjamesbibleonline.org
Start with Proverbs because:
1. It has 31 chapters, which make a monthly goal of 1 chapter per day to complete the book easy to achieve.
2. Most chapters are short.
3. Every chapter is interesting and most cover multiple topics.
If you get real motivated, then add a chapter from John's gospel. However, I would start with the easy to obtain goal of a chapter from Proverbs every morning. Then, if you want to read John in the evenings after the first month. Don't be hard on yourself if you miss a day or three. Just pick up where you left off. The brain and yes even the spirit has to be exercised like your muscles to gain strength. It will in time as it established this pattern for good spiritual health. I pair a couple glasses of water and my morning routine of coffee with my Bible time. This helps me to stay on track because I have already established the other positive habit. You might have a routine that helps you.
Here is a blessing to go along with your routine. Someone cared enough about me to share this message. There's a prayer at the end. I would listen twice when it's quiet and if you have any questions just ask me anytime. Have a great week!