If you have a plain patch file, recognized by its extension ".utp", you need a DoPatch to apply them. Anyway, executable patch files are in fact compatible to plain patches and can be applied using DoPatch the same way as plain patches rather than executing them directly, if you wish to.
To apply a patch file, DoPatch needs to know which patch file to use and which directory / file you want to patch with it. If you do not know where that directory / file is, you may easily locate it, using option "-auto" which will make DoPatch behave like executable patch files and auto-find the patch target for you on your partitions / hard disks)!
You may supply option "-t" to see, if a patch is applicable without actually applying the patch and giving one more filename/path, you may choose to create files in another place. But beware that if the creator did not use option "-f" to ensure that the patch includes information about files not changes, these files will not be copied along while patching and the directory might not be complete then.