Bit of a strange question about access…because if you open the bonnet, you can see the belt and its route round the pulleys quite easily.
I have not yet changed my belt but keep a spare under the passenger seat together with a sketch of the routing.
Changing the belt should be a 5 minute job. The tensioner on the near side top of the engine is spring loaded, so merely apply a turning moment to the 15mm bolt to release tension is all that is needed. (longer spanner the easier it will be)
It will automatically apply the correct tension when released with new belt in place. Check point: make sure the belt is running in the correct/same ribs on each pulley before finishing.
