I remember reading some of your earlier posts,
@Lindatype1 , and I believe your husband is Type 2, and on basal insulin only (no short acting) while he recovers from cancer.
Unfortunately there is no short answer to how many carbs someone should be having, it depends very much on how the individual responds to carbs, and what medications they have at their disposal for helping control their blood sugars.
It looks like he has a Blood Glucose meter. Have you tried testing before a meal, and then testing two hours afterwards to see what effect the meal had? You are looking for a rise no greater than 2-3mml by the two hour mark. Then if it’s within that range, you know that meal is fine. If there’s a bigger spike, you may want to look at how much carb he ate at that meal, and what sort (some take longer to get to the system than others).
I realise diet may be difficult, if he is waiting for a stoma reversal. Have you had any contact with whoever deals with his diabetes either at your GP or at a hospital? There really should be a DSN (Diabetic Specialist Nurse) who can advise on diet. or tweaks in his medications to get his numbers down so that he can have his op, but you may need to push to get someone to listen to you and give you the help he needs.