Speak to his Doctor. They can arrange for District nurse to call. They will ask how many times he would need changing during the day and night. They allow 1 for during night and 3 during day, ( that's my allowance, but, others may be different). They will give you advice on the subject. Delivery is every 90 days, and, free on the NHS.
There is a choice of Pull-ups, slips (which look like baby nappies) and pads which fit inside elastic knickers. I find these tend to fall down, so I place a pad inside a slip during the day, and as it doesn't get wet, with the pad being inside it, I use that for during the night
I find the Doctor is very helpful, I asked about a reclining chair on a Friday for my husband, and, it was delivered the following Monday. They arranged with Council for hand rails on stairs and in bathroom, and, outside front door, also supplied a wheelchair. At first he had a walker supplied, when first finding it difficult to walk, then 6 months ago, when he wasn't able to stand, for me to change pads, and wash/dress him properly, they arranged for me to have a hoist. A God send.
I have protective bed sheets with flaps. the centre square is quilted on the top, with waterproof material under it, to save the bed getting wet. I buy these myself, but, well worth it.
I hope everything works well for you, and welcome to TP