This is not true. Catching one strain of COVID does not necessarily protect you from the next strain, but getting vaccinated for that strain does. If you catch COVID unvaccinated, you are 10x as likely to die, 7x as likely to get myocarditis, 3x as likely to get Long COVID.
https://ourworldindata.org/grapher/united-states-rates-of-covid-19-deaths-by-vaccination-status
https://pmc.ncbi.nlm.nih.gov/articles/PMC9467278/
https://academic.oup.com/ofid/article/11/2/ofae039/7585852
Please do not spread misinformation. You do not have the education, experience, or the training to dispute the experts, and your attempt to do so is just pure arrogance.