Thank-you for your question. There are many different routes by which foreign nationals can enter and remain in the UK, all with different requirements. A good place to start is to take a look at the website of the UK Border Agency. This provides a useful outline of all the various immigration routes and the requirements of each. The website is available at:
From the information that you have provided it seems that the visitor categories will not be appropriate because they will only allow you to stay in the UK for a limited period. It also seems unlikely that you will be able to enter the United Kingdom solely in order to settle with your family members. This route is only available to foreign nationals who wish to enter the UK to join their husband/wife, unmarried partner, parent(s) or other relative(s) upon whom they depend financially. Therefore, you should probably be looking to enter the UK in order to either study or work.
If you wish to enter the UK as a student then you should apply under the Points Based System for entry clearance as a Tier 4 (Student) Migrant. You can apply for this visa 3 months in advance of the course starting. As a Tier 4 (General) student, you must score 40 points in the UKBA's points assessment. You can score 30 points for having a valid confirmation of acceptance for studies, which you get for studying a course at an acceptable level with an approved education provider (also known as a 'Tier 4 sponsor'); and 10 points for having enough money (also known as maintenance or funds) to cover your course fees and living costs. For further and more detailed information on the specific requirements I suggest that you take a look at the following area of the UKBA's website - hopefully this will provide all the information that you require:
http://www.ukba.homeoffice.gov.uk/studyingintheuk/adult-students/ At the end of your period of stay as a student, you could then apply under Tier 1 of the Points Based System for further leave to remain as a Post-Study Worker.
Alternatively you may wish to consider entering the UK for the purposes of work straight away. If so, you will have to apply under either Tier 1 (Highly Skilled Workers) or Tier 2 (Skilled Workers) of the Points Based System. All the information that you should need on applying for a Tier 1 (Highly Skilled Worker) visa is available here:
http://www.ukba.homeoffice.gov.uk/workingintheuk/tier1/general/ All the information that you should need on applying for a Tier 2 (Skilled Worker) visa is available here:
The UKBA has a tool which allows you to calculate how many points you may get, and indicates whether you may be eligible to work or study in the United Kingdom under the points-based system. It is available here:
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