What kind of coins are we talking about? I can only tell you about cryptocurrencies - digital coins. You can wait for a favorable price, buy cryptocurrency, and then sell it. I would start with the cheaper options if you are new to the subject. Buy bitcoin or ethereum. Well, if you have big plans and are not afraid to take risks, then it’s better to start mining, of course. To do this, there is a bitcoin mining hosting service https://minery.io/, where devices are remotely placed on professionally equipped platforms. This is the most profitable and promising.