Sick apple tree

[KAM]

I have an apple tree (possibly planted in the 1960s) that we have built our deck around, 3years since moving here the tree is healthier than it was, however it is still sick and I would like to know what I am dealing with and how/if I can cure it?
I have been treating it for powdery mildew and wolly aphids, the leaves being to curl over and form a white powder not long after budding, the bark is starting to split in places. Apples were small, red crispy and sweet but last year they grew massive and stayed green and formed scabs. Photos attached, please help I would REALLY like to save this tree

[JONA]

Several problems Kam..as you are aware.
First the two main ones.
Mildew...
Pick off any shoots and buds that are showing the powdery appearance.
In the spring spray with a fungicide as soon as leaves start to appear.
Repeat every two weeks.
At blossom time pick off any flower trusses that show mildew. This is the maximum time for spread of the disease. Called Primary infection.
It’s at this stage that it then infects the leaves for later infections known as secondary mildew.

The trunk shows signs of canker.
Scrape soft damaged wood back to clean undamaged wood. Paint with a good quality fungicidal paint.

Wooly aphid. Dap with a brush dipped in methylated spirit.

Spots on the apples is caused by scab.
The fungicide spray you use for mildew should control this too.