Questions for a newly funded startup

Hello everyone! I wanted to ask a question to the community as I know there are a ton of experts on here. I’m a startup founder who is about to raise a little funding and launched an MVP. The MVP was built with React on the front end and is a very simple web app at this time. Do I just add this new site on Google Search Console? I was curious about where to create blogs for the best SEO. Should I create it in webflow or blogspot and not link it to my domain at all? I had an issue at a previous startup where I had a Squarespace blog that was accessible through a link on my main site but was getting canonical errors as the squarespace blog was redirected to from the main site. I just don’t know where to start creating blog articles. Thank you!