Foreign Child Registration

Hi everyone, I'm trying to get some answers on a subject which may be new to most of you,

I am English, I married my Indonesian girlfriend in BKK under Thai law, and we are based here now with intentions of setting up business here and in fact have now started studying as to how we go about it.

We had a baby 4 months ago, born in BKK Bumrungrad hospital. On the birth certificate issued by Bumrungrad, there is a personal number written on the top right hand corner, which the local amphur where we were married said is a Thai personal number which means in the future our son can get a Thai identification card, and that he can own land and do most things that a Thai national can do.

Our son is not yet registered at the British Embassy although we intend to do that so that he may become a British citizen.

My questions are;

Is it correct that he may obtain a Thai ID card, and if so, when?

Does this mean that I could buy land in his name?

If I visit UK with him on his future British passport, upon re-entry he would get a stamp in that passport for 30 days. Does that mean I would have to do visa runs with him, or is he allowed to stay here for a certain ammount of years. I intend for him to go to school here.

Can anyone help or point me towards a lawyer who can?

Thanks