Did you get that roof fixed? ;>)
You have to round these figures out a bit, and you always needs a few extra tiles in case of breaks or bad cuts.
So your 9ft 7 ins X 1ft 2ins is 10 foot x 1.5 feet is 15 square feet, or 1.66 square yards.
Your 3ft 2 ins x 1 ft is 3 square feet or .33 square yards.
Add the 2 together 1.66 plus .33 and as near as makes no matter, you want 2 square yards. I just had a quick check and wall tiles are packed in Square FEET. You need 18 Square Feet. box ceramic wall tile Google Search
If you are careful, one box like this will do as it 17 square feet.
Description This cream-colored wall ceramic from Bravo has a glossy finish and is made for interior use. One box contains 136 3" x 6" tiles and covers 17 sq. ft.
Get yourself a notched trowel to put the adhesive on.
And a grouting squeegee to spread the grout.
And one of these to smooth the edge of the grout into the joints.
Another consideration is that some tiles are self spacing, but on others you need to use spacers to have a gap between them. Link in this article.
If you have to cut tiles, tile cutters are expensive, but the big box DIY stores will rent you one.