It would help if you also had sawdust or wood chips. Preferably fruit trees - apples, pears, cherries. Oak and beech are also suitable. But even here, you can find a way out because, in the field and green, alder twigs give excellent results, except that the color is very saturated. You can easily find all that in any big supermarket; they will provide you with defrosted or even cooled trout. Of course, if you have a trough and you smoke two salmon half-poods, you need more sawdust chips, but we all count for one sea trout, roughly 2 kilos. It is quite possible to do with foil, but you can go to smoking on an industrial scale if you find an old trough or a large basin. And in general, there are a lot of recipes at https://newbiedeals.com/recipe-boxes/.