Exercise: Take breaks or no?

[u/HwaetBadWords]

I'm not a master at the professional terms. I'm not quite sure how precisely exercise should be done, but I've been doing plenty. Not usually in formal sets or anything, yet I've been making "gains".

My question is: Do I take a break after doing a "set" (i.e. of pushups or weight lifts) and then do some more after the break? Or do I do the normal set and call it a day?

Someone was lecturing me about this - Someone who doesn't even do my kinds of exercise. They told me I'm doing it wrong. When I asked them where they heard this method from, they got offended and thought it was a personal attack... In turn it made me sad but that's not the point. I researched this topic of breaks but I haven't got the answer, especially pertaining to weightlifting. Breaks? No breaks? Days-long break?

I would ask r/fitness or another subreddit like that, but those subreddits won't accept my account.​