I am trying to click on save button on a popup on the same window, the popup also has a text box, to which I am able to successfully send the text, but when I attempt to click the button, error comes as element not visible
Element not visible exception can be resolved by using Explicit wait. Explicit wait in selenium will wait until the element is visible. Once it's visible you can perform the necessary operation.
Syntax for Explicit wait
WebDriverWait wait = new WebDriverWait(driver,30);
WebElement e = wait.until(ExpectedConditions.visibilityOfElementLocated(By.xpath("your locator value")));
In the above code selenium will wait for 30 seconds until the element is visible and once it is visible, selenium will perform the required action on it.