So you want to help but do not know where to start:
You could check in and see if they needs any assistance accessing services? It is hard to know what would work for them but generall 211 is awesome and can be called from any phone. Also online: https://win211.org/
Tbh usually if they are still outside at this time of year something is stopping them from accessing services so they might be frustrated about it but I know you can approach it with gentleness. Sometimes i just ask if they know of a couple places to gauge. Also, sometimes folks need someone to go with them to access services, gatekeepers can be traumatizing.
(In Seattle) Sound.Health. is an access point that i have heard mixed reviews of but can do more wrap around care for cognitive difficulties. DESC.org is another shelter. There are a few others. I have been updating Rad Care’s page with more info but here is the shelters page that has more info. I need to add there is a low barrier shelter that just opened up at Harborview. It should be up on this page shortly. http://radicalcare.org/resources/seattle/shelters/
If you gift them things, it’s likely best to make them secondhand, going to a goodwill or value village and getting some things that he could use is a cheaper alternative and also allows him to feel less bad if the items get left behind or crapped up. Also they might not have a place to store stuff. If in a position to do so offering some kind of storage for things if they might want somewhere stable to keep stuff so they knows where it is while they are elsewhere. Even if you have a job and are homeless this can be an additional obstacle. To expand a bit part of the struggle is that things get wet and there is no real way to get them dry and if you have nice things they get stolen. It is a labor of love to meet people where they are at and also recognize that sometimes folks are where they want to be at. Also if they wants to be connected to services, we are more than happy to do everything we can to assist that happening.