This question reminds me of a very important English point that I was to tell you about.
Happy Saturday, Everybody! What are you plans this weekend?
When you are talking about doing activities, say “I have plans“, with an “s”, even if you’re talking about doing one activity.
When I hear non-native speakers make a mistake by saying "I have a plan this weekend", I feel so bad for them, because it makes their English sound a little bit unnatural. :(
I’ve seen people with very high TOEIC and IELTS scores who still get this wrong, because it’s not at all what you would expect, based on the rules of English grammar.
Please watch the video to learn more, or visit my blog post here: https://www.tv-esl.com/i-have-plans/