Combining two different Rails projects?

Question

Ruby on Rails

Good afternoon! I'm learning Ruby on Rails, I wrote a Blog, and also a forum, as two completely different projects, now I want to combine these Two projects into One, so that the Blog and the Forum are interconnected.
That is, they had: one account on the blog and on the forum, for example, as in Google services.
It was made as one site. for example site.co/blog and site.co/forum with the same domain, can this be done without rewriting the projects?