Multiplying Cells by a Stationary Cell; IF formula, then multiply, and otherwise

Hi.

New to excel. Only know the basics.

So I want to clean up a cost-pricing spreadsheet for a cafe I made, which I've attached an example of.

PART 1 - Multiplying all cells in a column by a stationary cell?
I would like to multiply all cells in column H by cell A6, without having to type it into each cell.

PART 2 - Formula for IF(CellC<VALUE;CellB*VALUE;otherwise return CellA)
I would like the cells in column H to first determine if cells in column F is less than 250, and if it is, I would like H cells to return the value of C cells * 250. If it is not less than 250, I would like the H cells to return the value of D cells.

Looking more specifically at my example, if the markup margin is less than 250%, I want the recalculated price to read the Cost + Overheads column price * 250%. If the markup margin is already 250% or above, I would like the recalculated price to read the sell price.

Let me know if you need any more info. Appreciate the help.

Part1: Cell A6 is text, multiplying anything by it will give you an error.
Part2: Your formula is correct except percentages are always shown *100, so to work with 250%, you need to use the number 2.5. You did that correctly in the second argument of the if function, but no the first.

Sorry, I'm not quite understanding what you want for part 1. Is it H2*B7 + H3*B7 + H4*B7?

Or if you just want to be able to copy the formula down a column, you would make cell B7 and absolute cell reference. To do this, put your cursor in B7 in the formula bar and hit F4. The dollar signs indicate an absolute reference, so when you copy down or across, that part of the formula will not change. For example, if you wanted to multiply the H column by B7 and put the results into the I column, you would type =H2*$B$7 into cell I2, then copy it down.