It sounds like there was two separate problems, white smoke due to a crack or head gasket and a worn timing chain that broke. There is also now a good chance of bent valves.

If the car is clean source a good used engine, install it and enjoy the car. If you want to fix it, get it in time and do a leakdown test to check for bent valves before putting more time and money in it.

Post pictures of the spark plugs as they came out.

Good luck!!!

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