it would help to know just how much 'down sizing' you intend to do. or what you believe you will take of your present outfit when you exit the country.
if for eX all your gear is sold here before leaving, there are a number of Integrated amps which have DACs on board, or as optional OEM add ons you could buy 'over there' that will support the electrical needs of that region and suffice as nearly a one box solution Hegel, Gryphon, etc.
add a laptop and some speakers and you could be set!
OP> My DAC does not have a USB connection. It has Inputs: two ST-type glass-fiber optical, two coaxial S/PDIF on BNC jacks, AES/EBU, TosLink optical. Outputs: balanced on XLR jacks, single-ended on RCA jacks
1) Are there adapters that can connect to the DAC on one end and the computer on the other?
this is a hardware decision. a 'bridge' of sorts at the very least will be necessary. either USB or Ethernet to which ever interface you prefer to use on your existing dAC that suits you best.
ripping CDs to FLAc will yield 'red book' files or 16/44.1KHz results which is typical CDP information it gleans off the disc itself.
every DAC I've seen supports Red Book files.
choices and methods in this area are vast and range in cost from moderate to quite pricey.
as already stated, you might choose to go with a one box media player/streamer renderer storage unit solution like Wolfe audio, Aurelic, Aurender, lumen, Sony, etc.
or merely go with a bridge to convert your personal confuser's USB interface to AES, BNC, etc. these bridges also will need to have various support for things such as DSD, MQA, higher definition file formats, (if desired) in accordance with the abilities of your DAC of course.
most all of the more costly one box solutions like Aurneder or Wolfe will support what ever you desire of file formats going forward, usually.
2) I have a PC. I have about 400/500 Cds to convert. Thinking of FLAC files. What is the best way to convert so that I can have a library from which it is easy to search for a song by a given composer and conductor etc?
this is often a two step situation. if there is never ever gonna be a change from Windows to MAC, ripping to FLAC will be just great. if you later choose to use a MAC OS then a third party app which supports FLAC will also be needed. the better ones are not free.
or you could just as easily rip to AIF or ALAC which are as well lossless file formats and have cross platform support.
one, ripping and tagging comes by a CD ripping app.
I would say get yourself a copy of dbpower amp. appox $36.
once Accu Rip is setup it will rip and identify each file by tagging it with meta data acquired from one of five different online resources. you pick which one suits you best.
two, once CDs are ripped, choose yourself a media manager player. app like Roon Labs, Audirvana, itunes, J River, etc. there are litteally tons to pick from.
some are subscription based and some are free.
all of these media players once installed will access the data your CD ripper applied during the ripping process and thereby enable you to peruse them all in various ways. by Artist, albums, genres, songs, etc.
if using itunes is a thought, then rethink ripping to FLAc as itunes won't support that file type. merely use AIF or Apple lossless ALAC, instead.
regardless the ripping choice, once you have begun ripping to an external Drive, get yourself a secondary drive and copy everything onto it thereby duplicating all of your files in two separate drives.
this is not just necessary but smart!! 400+ CDs is a lot of time and effort. you'll not want to be forced to repeat this process if it can be avoided and redundancy can prevent it.
3) Cd player is something I can safely get rid of if I am not going to carry all these CDs abroad. correct?
as was said, why?
keeping a very nice CDP as you presently own is a no brainer. CDPs offer something else that file playback typically does not afford.
Depth of the soundstage.
4) Is there any device that can serve as a DAC and also as an amplifier that can connect to speakers?
this is a needless step unless you simply want to make some wholesale system wide changes.
if so refer to the idea on an Integrated amp, ie., NAD, Nu Force, or receiver, etc.
the most minimal outfit would be your laptop, your exteranl drives with your ripped files, and a USB head phone dAC/amp and a nice set of head phones.