New to seo

Hey guys! I'm about to launch my app, landing page, and blog. I'm curious if you guys have a good resource for reliable SEO information, any specific applications you use for your blog to improve SEO, or tips for getting more traffic to my app. This is a process I am wanting to learn ony own, I'm not wanting to hire anyone right now. Send me your tips or resources, as well as software you've personally used and you would recommend using.