I only have 2 sound sources and 1 video source going on this 3-minute YouTube video I'm making, but the orange line appears, and my song keeps jamming/stopping!
why does Adobe Premiere Elements 2019 have room for 3-4 videos and 3-4 audio/sounds when the presence of the orange line seems to be a warning that this program can't even handle half of that?
Whether or not you get the orange line (meaning you need to press enter to render for smooth playback) depends on several factors including:
Your computer specs, including hard drive(s)
The properties of the media (file type and codec)
The effects and transitions used
Whether the media properties match the timeline properties
The number of tracks used
In addition to what Bob said, consider that the orange line is a signal that your computer might be struggling to make the real time preview used during the editing process. "Rendering" with the render button or Enter key tells the computer to make a new preview file for your editing work. When you are done with your work the Export & Share process takes time to read each part of your source files from scratch to make a video to your output specifications.
This is the same question you posted a few days ago and it was already answered then.
Please don't double post a question to the forum. It makes it very difficult to track the conversation and keep track of which questions have been answered.