HMO planning permission required?

Hi all, I am in the process of buying my first HMO and I had few questions. the property is outside article 4 and if I convert this property to HMO will it require planning permission?

I understand that I need to have all health and safety requirements and landlord HMO license but apart from this what else is required from the council if the property is outside article 4?

Also, at the Lower floor I am planning to convert the kitchen to Bedroom 6.

At Ground Floor convert Utility room to a Bathroom and make new entrance to lower floor.

What approach would you have to this floor plan?

you have the toilet in the basement you do have drains for the waste at that low point?

only 2 bathrooms for 6 beds?

2 bathrooms
1 ensuite

Yes, in lower floor bathroom-shower already exists

check all with LA for permisions