Time intelligence functions compare periods: year to date, the same period last year, the previous month. They need a proper date table, with one row for every day and no gaps, marked as a date table so Power BI knows which column holds the dates. In Table view, select the Date table, then Table tools > Mark as date table.
Always give these functions the date table's column, not a date column from Sales:
Sales YTD = TOTALYTD([Total Sales], 'Date'[Date])
Sales LY = CALCULATE([Total Sales], SAMEPERIODLASTYEAR('Date'[Date]))
Power BI writes the column as 'Date'[Date], with quotes, because DATE is also the name of a function.
Month names sort alphabetically unless you tell Power BI otherwise, so April comes first. Select the Month column and set Column tools > Sort by column to Month Number.