I've no idea if this is basic or what but I have this data that contains multiple lines (forming a polygon shape). I want to convert those lines (multiple - each with a start and end point) to a single line. I tried dissolve, multipart to single part etc. I cannot use topology since it influences precision. I have zero knowledge of programming.
If your lines are already in the same data layer, then you won't need anything from the toolbox -- just use the Editor, and follow the instructions in "Merging features in the same layer."
If you have different layers, first Merge them into one layer (Data Management | General | Merge), and then merge the features together using the Editor.