If the original poster's goal is just to learn about things, this seems like a good answer. I would recommend trying one new thing at a time, though, rather than trying to do it all in one experiment. So if you want to move from your current vanilla html/js/css to a multi-tier-with-database, some framework (react/vue/whatever) and containers...pick one to start with.
You could, for example, deploy your existing simple stuff using k3s, a single-host, local, simplified kubernetes. Or spend $10-$30/month on a cheap hosted k8s instance, like digital ocean.
Or, leave your deployment as-is, and just tackle moving from vanilla html/css/js to vue or react.