Photo storage - apple

[EagleOnTheWall]

I have loads of photos and videos of the DC (~900GB) on an external drive linked to an old laptop.

I've now got a new computer (Mac mini)
DH said I should export my library and set up a new one as this will take up less space and I can put it in the cloud.

I exported it, the folder is ~800GB. Our family cloud is 200GB. So...

1. should I keep my library on my external drive but open it with the new computer or should I set up a new master library and import all the files I exported?

Then:
2) should I make a second library of favourites to sync to the cloud?

• I know you're going to say delete the photos but I have a very shit memory and can't picture things in my head. I don't want to delete pictures or videos of my DC. I need to be able to refer back to my library sometimes.

If I make this second library of favourites and sync my phone to this photos library, then all new photos taken my phone will be in this synced library won't they?

If I then connect my phone to the computer will I be able to open the master library and import all new pictures? Or will it get messed up?

If I open my phone in image capture on the computer, will it just show the photos the phone has taken or all those on the cloud too?

Watching with interest

Personally I would copy across to the cloud via MacBook, but keep them on the external hdd as a back up as well.
eta: I can never delete photos either. Besides, far too many to go through to even make that a practical solution. We have a family cloud storage plan, I think 2tb, as I was running out of room so instead of upgrading my own plan my dc added me to theirs. I have also recently had to give in and upgrade my Google storage after at least a year ago running out of space so no more photos, videos, emails etc. Think that is only 1.79pm, but is handy to have that email as an extra again. I do also have a separate laptop (so very very rarely used) along with an ext 2tb hdd which has everything from that laptop on - many years of photos and videos included. All of which are separate, and in addition to the ones on iPad/phone Google and Apple clouds!

I would

1. increase the iCloud storage
2. Copy every thing to Photos on the Mac mini, ensuring the library is the system library that is synced to iCloud.
3. Delete the superfluous images