If you're a student who's a citizen of the EEA or of Switzerland, you can apply for a free European Health Insurance Card (EHIC) in your home country. This card will entitle you to free health coverage throughout the UK.
If you applied for a Tier 4 visa in your home country and have obtained a visa for more than six months, you'll have paid the Immigration Health Surcharge as part of your visa application. This payment allows you to access NHS healthcare in the UK at no additional cost.
If you're a student who will be in the country for six months or less, or you don't qualify for either of the above options, you'll need to take out private medical insurance to cover any healthcare charges in the UK. This can be arranged in your home country.
If you already have medical insurance in your home country, ask if it will also cover you for the UK. In most cases, there will need to be an extra charge.
When you use any medical facility in the UK, you'll be charged the full price for the treatment, which you can then recover from your insurance provider.