Every old boat is not a candidate for restoration. Some are not worth the effort and the money. Any advice you get here, including mine, suffers from the shortcoming of not being able to see the boat.
Glassing up a hole in a fiberglass boat is no big deal if that is all there is. But a boat that has a hole and extensive cracking may be suffering from damage inflicted by an accident and/or the effects of aging. The damage this boat suffers sounds like it came off a roofrack and landed in the road.
Your job is to look at everything and decide whether you are willing to invest the time and the money to fix everything. It may take a lot of grinding and dust eating and the application of a lot of expensive resin to bring the hull back. And, because this is an old boat, you may end up with an outdated and inefficient hull. Kayaks have come a long way in the last 30 years.
I recently paddled an Old Town "Otter" that a relative won in a raffle. It wasn't a world-beater but it was comfortable, made of polyethylene, and can be purchased new for $299 and used for about $100. It would cost me way more than that in materials to build an simple S&G kayak.

: Hi i am about to get hold of an old kayak that has a few repairs needed on it
: and im hoping that someone can help on the best way to fix these.

: [1] The bow point has a hole where it was clearly rammed into a rock. The
: hole is about 5 cm in diameter.

: [2] The kayak was made in two halfs and then joined by some method. Then the
: owner finished the job by using a sealing tape around the full
: circumference of the kayak. The tape needs replacing and underneath it
: where it has worn away there are chips out of the fibreglass. Theses would
: be about 1 mil deep.

: [3] On the bottom of the kayak there are some small cracks ,and There are
: also two farily large chips of about 6 cm in diameter and about 1 mil
: deep.

: What is the best way to fix the joining and the cracks.
: thanks for your help