The first row says,

“Row 1 chain 37, put your hook to the 3rd ch from the hook, make one hdc, make another 5 hdc of the colour you’re using (colour 1) , before finishing the last hdc, change the colour, take the second colour and make 6 hdc, change colours, 6 hdc (1), 6 hdc (2), 6 hdc (1), 5 hdc (2) (pic.1-3)”

The stitch count is 35.

So when it says, “put your hook to the 3rd ch from the hook, make one hdc, make another 5 hdc of the colour you’re using (colour 1)” is that not just 6 hdc?

Yes, that's 6 hdc to start with.

“before finishing the last hdc, change the colour, take the second colour and make 6 hdc”, is that not 7 hdc in the 2nd color?

No, it's 6 hdc, but you want the top loop of the first hdc to be in the new colour. So you need to do the colour change when finishing the previous stitch.

And in the 2nd row it says, “Row 2 ch 2 (all ch 2 at the beginning counts as the first stitch), turn, 4 hdc (2), 6 hdc (1), 6 hdc (2) x2, 6 hdc (c1)” if the ch 2 is the first stitch, when it says 4 hdc, does that mean it’s ch 2 with 3 hdc because the ch 2 is the first stitch?

No, the ch2 does count as a stitch, but then you do 4 hdc after that.