Your questions here seem to be similar to your other thread: from venezuela want to go switzerland
And here is another thread (with links to yet more threads) with tips for others in similar situations. Looking for anyjob please like cleaning or anything.!!!!
Here - in Italian, maybe you can more or less understand that through your Spanish, or Google translate will help - is a site with standard suggested budgets. For you and your brother, you could look at the budgets for a couple, to get a basic idea. If you are prepared to live without any luxuries, and buy everything except your food second-hand, and to walk and travel by bicylce, it is possible (though not easy) to live on less.
Therefore, yes, if you both managed to work in unskilled jobs, and you lived together, then yes, you could cope financially.
We have no legal minimum wage, and the range can be quite wide. A cleaner, for example, can earn as little as Fr. 16 or Fr. 18 per hour if he or she works for a cleaning company or through an agency, but up to Fr. 30 or Fr. 35 if working for a private person who knows and trusts them and who appreciates the quality and speed of their work. An "assistant" (a new type of job, funded by the state disability office) is a person who provides household care, runs errands, cooks and perhaps provides basic nursing care for people with disabilities, who live in their own homes. The range there is around Fr. 20 to Fr. 28 per hour.
Besides living in a flat of your own, you could also consider renting a room in a shared flat, with other young folk. That is very usual here, especially but not only for university students, and can be a much cheaper way to live. See, for example, http://www.wgzimmer.ch/
In any event, I'd recommend that you join www.couchsurfing.com
(free) and make proper, full profiles (to see how to do that so that people find you interesting and want to meet you, read lots and lots of other profiles). Couchsurfing is an easy way to make good connections as soon as you arrive, and not have to stay in the youth hostel until you find a room or a flat.
Apart from accommodation, the other big cost is compulsory medical insurance.
You might also benefit from the experience of Etefan02, who has dared to do the same sort of move as you are considering, and is already in Switzerland: Guidance needed- [Swiss citizen abroad considering moving to CH]
If you are not in a hurry to leave home, then I'd recommend that you do as much as you can before you leave to acquire skills which will save you money when here. If you can't already do these things, then learn
a) how to cook good, nutritious food. Eating out, even in snack-bars and canteens, is disproportionately expensive to buying groceries and cooking at home. Meat is expensive, so it's good to know how to get sufficent protein from other sources. Here, you can drink tap water for free. 500 ml of Coca Cola can cost approximately (in very rounded numbers) Fr. 1 or Fr. 2 in a supermarket, about Fr. 3 or Fr. 4 at a take-away stall, and Fr. 5 to Fr. 8 in a Restaurant.
b) how to take care of your clothing, washing, ironing and mending
c) general handyman skills to repair furniture or other household items
d) how to ride a bicylce
e) how to repair bicycles
f) get fit so you can walk a lot; it's a great way to discover places and settle in.
And more important than all of these, start learning German before you arrive here, from online sources if not from real people who already speak it where you live.
If your mother or father, through whom you have your Swiss citizenship, or your Swiss grandparents, have any relations or friends in Switzerland, try to write to these people to establish contact. A lot in Switzerland happens through knowing someone who knows someone...