There are replay functions (and plugins) available to repeat a short sequence while recording or streaming.
Due to the nature being 'live mixing and broadcasting' of obs there is no possibility to pause and edit (so to delete parts of) during the recording or streaming.
If you're just recording offline, finish your recording with all the outtakes left in, then have a look for a free video editor and do (after recording at all!) cut off the outtakes you produced. There is a big range from avidemux (with a gui) up to complete NLE (non-linear editing) software at hollywood's standards like Davinci Resolve.
