Your options for leisure activities will depend on what you like. Huelva is not a big city but there are many plans going on, including opportunities for outdoor activities.
Where you choose to live will obviously depend on your personal preference. However Spanish tend to be active and sporting activities are popular among students. Sporting clubs and societies organize a wide range of activities. Taking part in these activities is probably the best way to meet new people and take a break from studying.
Other natural meeting points are clubs and pubs in La Merced or Downtown. Many of these serve drinks and food at affordable prices. The legal age for drinking in Spain is 18. Some establishments may only admit people over 20 or 23 years of age.
A lot of people go out for a drink at the weekend, and there can be long queues from early on outside the more popular places. Some nightclubs charge an entrance fee, usually ranging from €5 to €10.
To find out where to go just ask a fellow Spanish student or check out erasmus groups on Facebook. As a student, however, you have an invaluable social resource in your class, ask to your classmates “where is the party?”