Sophia here from Shopify. Welcome to the Shopify Community!
I would love to help you get your online store looking just the way you'd like it. With most themes, you'll be able to edit the text under Online Store > Themes > Customize > Theme settings > Typography. Do you remember if this is where you originally edited the text? It sounds like there might be an admin or browser issue going on if you're being redirected to an unexpected page, and we can definitely take a closer look into that.
Can you tell me a bit more about which text you're trying to change and which settings you are navigating to? It would be helpful for me to have the following information:
Feel free to upload screenshots here to show me what the admin settings and storefront look like for you.
I'm glad to hear that you found a workaround for now! However, expected behaviour for the theme editor—when you navigate to Online Store > Themes and select Customize on the current theme or Actions > Customize on an unpublished theme—is that it will open in your current browser tab. If that isn't happening, there might be a browser issue.
Let me know which browser and device you're using, and I can ask our Technical Support team about it. In the meantime, I recommend clearing the cache and cookies and ensuring that you're using a supported browser that is updated to the latest version.