Treating my wooden worktops and pine cupboard doors

I would recommend using Osmo TopOil for worktops, it comes in a range of colours including clear or natural and is food safe. Make sure to read the tin as some worktop oils are not food safe. For the units and doors I would suggest clear Liberon quick drying tung oil.

You can use that.But I prefer pure linseed oil on my worktops as it penetrates deeper yes

linseed oil is best if find better resistance to water

Hi in my experience pure tung oil gives a better finish than the quick drying tung oil, but tung oil is definitely the best way to go. The first coat should be diluted up to 50% with white spirit this helps it soak deep into the wood, then at least another 2 coats should be applied after putting each coat on wait about 30min or so and wipe any surplus off. It's time consuming waiting for each coat to dry but it's worth it.