You are a Private seller so there is no facility for you to leave this notice, it's reserved for business sellers on eBay.
There is a Time Away function, link below to explain, but personally, I always felt it was best to end all items, they then go into your unsold list for a maximum of 90 days if you are on the Seller Hub, for you to relist them from there at anytime, in that 90 day period.
Time Away explained here:
https://www.ebay.co.uk/help/selling/selling-tools/time-away?id=5137&st=3&pos=1&query=Time%20Away&int....
@sputnick57-0