You have to understand that a sufficiently high UBI is very expensive. It either costs trillions of dollars or will be so low that poor people may be worse off than now due to lack of other welfare. Realistically affordable UBIs would amount to less that what jobless people get on social welfare, e.g. around 200-300 EUR in my country. I've seen the figures, and those were the ones of proponents of UBI. Do your own calculations and you will see what I mean.

If you want to help poor people, start with radically capping and reducing rents per m^2 everywhere. And by "radically" I mean radically, not just halving them. That's one of the biggest problems in almost every country and it will get worse and worse if current trends continue.