Do you think it's okay that I wash my feet in the sink before I take a bath
If the sink is cleaned afterwards then I see no issues with it.
Because I take a bath when I am drunk.
If you are drunk can you not wash everything in the bath? That would make it easier for you and to avoid slipping on the floor.
Washing in the sink isn't the best but it's fine.
If you think you can handle it then it's okay. Maybe your feet will be more pampered this way than in the tub. Then maybe the rest of you won't be contaminated too in the tub from dirty feet.