Just try.
We used a potty chair with both our kids. We just put it out wherever they were, whatever room. And left them naked on the bottom at home.
BUT the bottom line is: we went by our kids' cues.
EACH kid is different, and per boys and girls.
My daughter potty trained early, 2 years old.
But my son, was ready, HE being ready... when he was 3 already.
But both, are normal.
Maybe, your Hubby got it into his head... because his Mom is telling him this???? (my MIL was telling my Husband, even if she lives in another country! So irritating...she's not my kids' Mom). Anyway, or maybe others are telling your Husband. Some Husbands, go according to what others are telling them or commenting to them. For example.
Your son is showing an interest. So maybe go with it.
But don't nag or battle about it.
It takes, TIME. Months even.
His being verbal or not, doesn't matter.
And, if a kid ain't ready... they won't.
It all depends on the physiological development of the child, not their age necessarily.
AND keep in mind, and tell your Hubby that:
nighttime pottying and nighttime dryness, are 2 DIFFERENT things and 2 DIFFERENT timelines. Nighttime dryness does not even occur, until 7 years old, and this is NORMAL.
So until then, nighttime diapers are used. And a waterproof bed pad for under the child.
AND tell your Husband, that even if a child is completely potty trained, there WILL be accidents, and some regression. All normal.
Children have accidents. It is childhood.
All my daughter's Teachers in Preschool/Kindergarten/1st Grade, ALL unanimously, said this.
Potty mastery goes in stages.
AND their physiological ability, to hold...their pee long enough to get to a toilet. For example: you are at a mall, at the checkout line, and THEN your child says "Mommy I have to pee.... " and they say "now...." and they are squirming. So then, you have to go quick, to a public restroom. Some children will be ready, their body, ready to hold it until then... and some cannot.
ALSO get a car potty, even after your child is potty trained. This is INVALUABLE, for when you are places there is no toilet or you are stuck in traffic etc.
Just go to Amazon, and search for "car potty." We kept these in our car and in Grandma's car. And all our friends had one too.
Keep in mind, that little kids, cannot hold their bladder, for long stints.
Tell your Husband, it can take time. Some kids longer than others. Some kids quicker than others. Its okay.
And you may have to stop and then revisit the process, again later.
Your Husband probably thinks it is a no-brainer, because he is not doing
it.
And last but not least:
For your Husband to know as well... potty training is NOT something to scold or punish a child over... if they don't do it like the adult thinks they should. And don't compare him to other kids.