I am not sure of the setting. For example, if you are trying to reassure a friend sitting with you in a restaurant, suggesting they stay seated and relax, I would say, " There is no need for you to worry. You SHOULD sit here with an easy mind and enjoy your drink". If you are the manager in the restaurant suggesting that someone sit while they wait, I'd say, " There is no need to worry. May I offer you a seat, so you can ease your mind and enjoy a drink?" You use the word "would" when things are conditional. For example, "I would offer you a seat IF there was one available". Hope this helps

There is no need to be worried. I can offer you a seat here. Relax and enjoy your drink. For learning: English

On the web, I find that "no need to worry" is more used but "to be worried" is a bit different I'd also say "and TO enjoy your drink", but in general it looks ok