First of all, relax. Nothing is too big to take your life, just relax.

Can you please tell where you live (at least the country)? This can help us find some right steps for next course of action. First of all, Did you have any insurances for your house or any of your products, if so, then start by contacting the insurer, and in these cases, they would just give you sort of settlement price, becaus efor most things damage is done beyond repairs. Most likely your clothes (at least the natural fabrics, like cotton) would be all ruined. But synthetic fibres, and even some of your musical instruments (non wooden parts) and even some pc parts (depending on your cases, and actual salinity of water) would be recoverable, so please do consider to collect them.

Don't worry and possessions, things can be replaced. You sound relatively young, you have many options!

If you have your stuff with you know you can ship it back to your family in Hawaii, before you travel. Or you can join a local Facebook group and sell it.

It sounds like you and your family is physically ok, that's great news! Build from that

I don’t really understand the sequence of events. What did you go to Thailand for?

You’re living at your mother’s house, was she not there while you were away?

The pump flooded while you were away? Then the power was also turned off while you were away? Was no one at the house when all this happened? Why did your mother suddenly sell the house? To recover some of the investment?

Either way, having been in a similar life circumstance, job wise at least shit will suck. However the suck will make the next phase of your life more that much more rewarding (not saying that will make it easier). Try to focus on getting to that part. I worked shitty jobs I hated until I got one in the field I wanted. If there no cs/tech jobs going work other fields. I kept side projects (relevant to my field) going while I work unqualified jobs and it’s what landed me my current position. If people won’t hire you to give you experience, do it yourself essentially.

See if you have any relatives/friends with some spare garage space to store your stuff. Sell what you can’t store. Even if you have to sell it all (bar the PC, as you should keep that to look for work). Shit is replaceable. Ideally what you sell can go towards paying bond on a rental. If you skilled in tech, consider starting your own business doing IT. That or a lawn care business. Print off business cards (cheap ones) and drop them in mailboxes. Until you have a job that can pay bills/rent; your job is finding a job. Stacking shelves isn’t glamorous but nor is being homeless.

If you do have money left or manage to sell shit buy a new set of clothes! Trouser, collar shirt (polos are good and usually don’t need ironing). Yes buy cheap ones but something with a collar will help. Only wear them for interviews and of all clothes, keep these clean. Buy an electric razor with a couple different guards (ideally number 1 for facial hair and 3 or 4 for head). Being broke/homeless grooming and clothes will be one of the bigger hurdle that fucks things up. Ideally if you avoid this and get a job warehousing, cleaning or hospitality usually are always looking for workers.

Your mom will come around. If im reading this correctly though she’s probably a bit fed up with the current arrangement as it clearly hasn’t worked out for her. It won’t be permanent. Our parent have their own mental health and needs to tend to as well. Even if she is prioritising hers at the moment, don’t read that as a reflection of her relationship with you. Certainly not in the long term at least.