There are a few best practices that you can follow to make sure your site is optimized for SEO
Make sure that each of your pages has an SEO Title & Description set up as those will be read by the search engine and will show up on the search results page.
Set header text for text content that represents headings of various levels on your page. That will help search engines better understand the structure of the page.
Set these tags for each of the images used on your page. This will help search engines understand what your images are.
For navigation within the site it's often better to use links instead of buttons. That's because links are recognized by the search engine as connected to a page they're linking to and buttons aren't.
Now that your content is optimized, the key thing that you have to do in order to be discoverable through Google is to make sure that Google knows about your site. On a high level there are 2 ways that you can do that:
You can wait for the Google crawler to come across a link to your content on other sites that Google knows about
You can tell Google about your site and its page
The first option relies on there being links to your site, which can take a long time to happen. So the second option is your best bet. Here's how to do that:
You'll first need to set up your "sitemap.xml" file, which is the file that gives Google the full list of pages in your application. Bubble makes it very easy to do so under the Settings tab.
Note that some of those pages will be static and some of them will be dynamic (i.e. product page). Luckily Bubble is smart enough to handle both.
Now that you have your sitemap set up, you should tell Google about it.
Create a Search Console account and add your domain to it. This might require you to verify the domain ownership as part of the process. Then, once your domain is set up, just add a link to your sitemap file, which will generally be https://[yourdomain.com]/sitemap.xml. Google will then take a little while (up to a few days) to crawl all of the links and discover their content.