Your starter must be rising in the jar, as this is how you’ll know it’s ready to use. If it is just bubbly but not rising, you need to feed it until it starts to rise in the jar. Then it’s ready to rise your bread. Take 1/2 cup of the starter you have, ( don’t use more than this) and 1/2 cup water and 1/2 cup flour. Stir all this together and leave on the counter for 8 to 12 hours and feed it again every 8 to 12 hours until really bubbly. Then it will be ready to make bread. Let me know how it does or if you need more help. A sourdough starter is like a pet and you have to feed it and make it strong and then it will rise your bread much better Check out my website for more info: https://www.culturedfoodlife.com/how-to-care-for-your-sourdough-starter.