Google Analytics is a powerful, free tool for tracking and reporting on traffic to your website from search engines and from social media. If you have and use a Google account, then you already have Google Analytics. To use it to track and report on your website traffic, you'll need to do a little more setup.
The Google Search Console is a webmaster tool that allows SEO to see all the search result of their website. This tool also tracks and reports page speed, links, and CTR. You can also set up goals and ROI from your campaign and track your website performance. It’s also free.
SEMRush is one of the best out there to use for keywords. They have a Keyword Analysis tool, a Keyword Difficulty tool, and a Keyword Research tool.
Screaming Frog is a web crawling and website audit programme that was created in March 2011. The programme allows the user to view the structure and size of their website as well as any SEO issues they might have. SEO issues include duplicate content, broken links, missing meta tags etc.
Keyword research is important for any SEO campaign, it's needed for content optimization, on-page optimization and link building. To do proper keyword research you have to have access to the right data. Ahrefs is the best tool for keyword research, it provides you with search data, social data, backlinks data and much more.