Look, and I know this is probably not what you want to hear, but why don't you spend a couple of days reading online resources and trying things out. This is better than opening a question for every upcoming problem. It takes time to get into a new method such as scRNA-seq analysis, but it is recommended that you first get familiar yourself a bit. There is also https://osca.bioconductor.org/ which extensively described single-cell workflows using the Bioconductor environment. For me this is way better documented than Seurat, and therefore easier to digest, better to get my head around. I strongly recommend it over Seurat, maybe give it a try, it contains lots of useful information and material plus example code. I personally found http://www.bioconductor.org/packages/release/bioc/html/scDblFinder.html helpful in my analysis.