You get an exemption on National insurance initially, I believe for the first 52 weeks for the main ICT visa holder only, not dependents if they work. Income tax you have to pay, there is no exemption.
https://www.gov.uk/tax-come-to-uk
When you do not need to pay
You do not need to pay National Insurance or get a number if you have either:
Portable Document A1, E101 or E102 that proves you pay National Insurance in another European Economic Area (EEA) country
a certificate from a country that has a bilateral agreement on social security with the UK
Ask the social security authority in your country for the document or certificate.
The countries with a bilateral agreement are:
Barbados, Bermuda, Bosnia and Herzegovina, Canada, Isle of Man, Israel, Jamaica, Japan, Jersey, Guernsey, Republic of Korea, Mauritius, Montenegro, North Macedonia, Philippines, Serbia, Turkey, USA.
You will not have to pay National Insurance for the first 52 weeks if you both:
are sent by an employer in your home country to work in the UK temporarily
come from a non-EEA and non-bilateral agreement country
https://www.thesalarycalculator.co.uk/salary.php