Hi, welcome to OSM. We do not map geocaches, it kind of defeats the object.
I have reverted this.

This is a garden, it is not a park

Hi, the railway stations should be tagged as Borth, not Borth Station. You have also changed it to a station. Borth is a request stop, hence it was already correctly tagged as a halt.

Hi, you seem to have removed the railway=rail tags from the Cambrian Line. I am fixing this.

Hi, does this church really have a postcode?
Any postcode is likely to be the vicarage, I doubt post is delivered to the church.

This is not a park, reverted

This is not a park, reverted

This edit is unacceptable. Reverted

This edit is unacceptable. Reverted

This edit is unacceptable. Reverted

Hi, welcome to OSM. The correct way to tag a school is on the area covering the grounds and just tag the building as building=school. The grounds here were already correctly tagged.
As for language you should not put Welsh and English into the name tag. here I would use Welsh as the primary and use name:en for the English name.
Keep up the good work, ask if you need any assistance.
Phil

Hi, the correct place to tag a school is on the grounds. Nodes are seen as a poor way to tag large areas. There was a successful project
There was no additional node however, there was a bus stop, which you have added school tags to. I believe that both these changes should be reverted.
Cheers Phil

Hi, please could you explain your reasons for deleting this churchyard?

Hi, please could you explain why you have removed the name from this school?
Thanks Phil

Hi, please can you make your changeset comments meaningful. Describe what you are actually trying to achieve. This and many of your other changes are huge and covers a very large area.
Thanks Phil

Hi, welcome to OSM. There is no supermarket here. I have therefore removed it.

Hi, this should probably office=company, it certainly isn't a clinic

Hi, please remember that that name tag should only be used for actual names, not descriptions. I an object doesn't have a name then the tag should be left blank.

Hi, please remember that that name tag should only be used for actual names, not descriptions. I an object doesn't have a name then the tag should be left blank.

Hi, this edit looks a little odd. Firstly is it a hotel or is it a holiday cottage? Also a name is meant to be a name and the tag should not be used for a description.
What is the source of this edit? I am assuming you have not been there as it is not near a building. Is it verifiable? Does it have a sign, most holiday cottages appear as normal houses with no signage so are not considered mapable in OSM.