How do you learn Japanese speaking?
Start with language you can use immediately. Learn a small set of high-frequency responses, combine them into reusable sentence patterns, listen to a short model, repeat it aloud, and then use the same pattern in a guided conversation. Speaking improves when each new phrase becomes part of a real task rather than an isolated item to memorize.
You do not need to finish every grammar lesson or master hundreds of kanji before you begin speaking. A better early goal is to handle a short interaction: greet someone, introduce yourself, ask one question, understand a likely answer, and respond politely.