So

I got married in Sept 2020 in CH and my B Permit has arrived last week !!!

I still have a UK bank Account , UK Family address (Mothers), and Swiss Address

Do I need to formally tell the UK Tax authorities (HMRC) That I am domicile in CH from married date ?

Can I still have UK bank account or do I have to transfer all money to CH ?

I guess I don't need to tell CH authorities that I am domicile here cos they issued me with the B Permit

All info appreciated

Tell HMRC

Keep the Uk bank account of you wish, you should inform them you live in CH

Can I still be registered for tax in both countries - I still have my house in UK that I rented out

You need to declare rental income in the UK, you need to tell them you are a non resident landlord or basic rate tax should be deducted by the renter / agent.

No, you can give them your new address if you wish, or a c/o your mother's address. This would be for correspondence. Giving a foreign address may help if there is any confusion about tax-residence later on but it's not essential. Your UK tax status changes depending on your circumstances and getting married won't change that. If you move away for full-time work then you become non-UK tax resident straight away unless other rules over-ride that. Otherwise it's based upon number of days in the UK etc. When you get married will have no affect. "Domicile" in general means "where your life is" but in the UK for tax it has a very specific meaning and at the moment is not relevant here.
You can but if you give them a foreign address they might decide they no longer want to let you have the account. You could however change your address with them to your mother's address or set-up a semi-permanent forwarding from your old home. In theory you should tell them if your tax residence status changes which it more than likely has as you're no doubt tax-resident now in Switzerland (perhaps in addition to being UK tax resident) however as long as you declare this account to the Swiss on the annual tax return there should be no problem.

With the rental income, in theory you should register as being a non-resident landlord but in reality as long as all or any tax is accounted for properly you don't need to. If your UK tax liability is 0 you don't need to submit any UK tax returns unless you are a company director or something like that. Otherwise you do and you'll probably want to fill out the "non-residence" pages if you think that you are.

All the info is on the HMRC's gov.uk webpages but as I said, if you have no UK tax liability you don't necessarily have to follow all the rules.

So my worldwide assets ( House , UK bank accounts and stocks and shares)
get taxed as Part of my Wifes C Permit Taxation

I pay UK tax to the Inland revenue for the income I get on my UK house

I am domicile in Swizterland

I have a Joint Tax reference number with my swiss wife ( ZPV-Nr )

So Country/jurisdiction of residence for tax purposes

Is it Both Switzerland and UK or can I just say Swizterland

I am filling an application for a swiss bank account

If you tick UK and Switzerland on the form, as a non-UK resident your UK bank account details will be communicated to your canton’s tax authority as part of automatic exchange of information

Read the statutory residence test to see if you are also resident in the UK, depending on your connections & how many days you spend in the UK.

On the assumption you are not dual UK/Swiss tax resident you need to tell the Swiss bank you are only Swiss tax resident, same for your UK Bank, if you fail to tell them they may freeze the account. I had a UK account with mail sent to my wife's house in the UK, NATWEST wrote to me believing I was tax resident in Malta & wanted a full declaration within 30 days.

Malta isn't Switzerland.

You need to declare to the Swiss all worldwide income and assets. You won't be taxed on all of it.
If you're UK tax resident you also need to declare your worldwide income.
If you're non UK tax resident then you need to declare if you would have a tax liability there e.g. because of rental income.

I think for the bank account as long as you have Switzerland and don't have the US then you should be ok.

I never said Malta was Switzerland Malta is EU, neither UK or CH is EU
OP has to declare income & wealth in CH, plus rental income in UK, if dual resident World wide income & capital gains but not wealth in the UK.

Simple really, gets more complicated if the OP dies & husband is not UK domiciled as the spousal full exemption IHT does not apply, just £55,000 unchanged since 1982 which is the same as the nil rate band at the time.