00 isn't part of the country code, it is the international dialing prefix for outbound calls from the UK. Since many countries use other international dialing prefixes, it is best to quote international telephone numbers beginning with a single plus symbol and the correct telephone country code; in this case, that would be +1 28.
Telephone country code +1 is North America, including the USA, Canada, and certain islands in or near the Caribbean. You need the next three digits to narrow down the location:
(The plus sign means "insert your international access prefix here." From a GSM mobile phone, you can enter the number in full international format, starting with the plus sign. The most common prefix is 00, but North America (USA, Canada, etc.) uses 011, Japan uses 010, Australia uses 0011, and many other countries use different prefixes.)
The country code and area code of Aberdeen, United Kingdom is 44, (0)1224.
The country code for the UK is +44. The plus sign means "insert your international access prefix here."
Country code +44 is the UK; 74 is probably a mobile.
Dialing from the USA, 00 44 would be UK. 00 is the international access code in USA followed by the country code of UK which is 44.
Australia uses country code +61, dialled as 0061 from the UK.
If the Dubai mobile has international roaming, it can be called by dialing the UAE number, country code +971. If you want to reach that phone by dialing a UK number, you may be able to swap in a UK SIM card.
No one uses that code to dial the UK, which is country code +44, not +55. '00' is a commonly used international access prefix, and +55 is the country code for Brazil.
UK
The UK
That is a mobile number - from the UK. This is distinguished by 44 - the country code for the UK, followed by 7. All the UK's mobile numbers start 07 - but when calling from abroad - you omit the zero
The code for the UK from any country is 44
Country code +44 is the UK, and +44 3 is an all-UK number.