It is possible to get meaningful results for your project only using free SEO tools. Tools like Ubersuggest are generously free. Google also has a suite of free SEO tools you can make use of like Google Search Console, Keyword Planner, Trends and Google Analytics.
SEMrush, which is industry standard SEO tool, also has a free tier. SEMrush's free plan is not advertised on their site but can be selected after signup. Free Chrome extensions like Surfer SEO, Keywords Everywhere, Mozbar and Serpstart are also helpful.