I understand your frustration as I mentioned earlier I have a high needs autistic child.
I don't think just from your post that your child is ND BTW, but some children just get into things more.
You have got 2 options:
Accept some things are beyond your control and let them go for the sake of your own mental health and accept that this particular child explores the world like this, or, remove everything that he can get into and only allow what you are willing, able and comfortable to be cleaned in that area.
You have acknowledged your own physical limitations.
This is what us disabled parents of high needs children have to do.
We bolt our cupboards to the wall, use mag locks, use disability support aids, like no spill cups and wipeable floor covers, baby gates, chains, play pens, rotate boxes of toys, remove things that can cause mess and stress in a matter of seconds and create a safe space where our children can be left unattended based on their concept of the world around them.
I do not think for a second you're a bad mum, I think you're great, I think this is just your first time experiencing a truly high needs child, and so you need really selective advice from other parents and peers with experience of high needs children.
You are tired and you are stressed and you have 3 children who are all asking you to pour from an empty cup in different ways and you are drained. It's understandable.
There are many practical solutions that have been offered without judgement here today though that even in the smallest of houses can be implemented.
Please stop focusing on all of the judgemental posts. You're letting them live in your head rent free when these people won't lose sleep over your circumstances tonight.
All children have sensory needs for input. I would look into the free online resources available for you to do a sensory diet profile for your child who is just developing in his own beautiful but chaotic way, and find ways to incorporate this into your days, whilst also making sure the space you're leaving him in while you meet your own needs is safe.