If you actually want mechanisms for being happy no matter what, start realising that none of the stuff you’re stating as issues actually matters, and you can work on accepting that. What does the walls have to do with your happiness? You control if you’re happy or not.
Stoicism-like ideas and reading can help (or at least do for me, minus the religious bits) with realising that external factors do not matter for your happiness. Happiness is 100% controlled by your mind. There are unhappy people who have all the things you say you lack and way more, and there are happy people who have none of them, and are in situations that are objectively way worse than yours, so the state of material things is not the defining factor for your happiness. The defining factor is you and how you choose to react to external things.