If the source footage is purely digital – you don’t have access to the original, this is all you have – then I’d say that the only thing you can really do in vegas pro is applying a Denoiser effect and if necessary Flicker Control.
Won’t get rid of the lines, but might clear everything up quite a bit.
You could try to duplicate the video track, offset it horizontally a bit and maybe with the right effects and compositing modes you can “improve” the look, but I’m fairly skeptical. That would more likely be a “different” look rather than a “better” one.
If you do have the physical source recording, then a lot of it is down to the hardware used to digitize this. Better hardware – better results, noticeable difference.
Alternatively you could try using some AI tools, such as Topaz. There should be a free trial available to test it out, but if you have any questions, don’t hesitate and head over to the AI forum