I have yet to subscribe to Adobe Illustratorand have never before used it.
Having said that, I have a project which I think I will need to subscribe to Illustrator for, which will likely take 6 months or so.
If I complete the project and then no longer need to use Illustrator for any other projects, will I still be able to access save and access my files/creations afterwards if I need to forward then to a distributor or printer.
Other rival graphics applications can import Adobe Illustrator AI files as well as files exported in EPS format. But they usually won't be able to open/import AI files saved in the latest version. If you save down to earlier versions (such as CS6) they'll be more likely to import successfully. But certain live effects and features in a Illustrator file can "break" when saved down to an earlier "legacy" version format. Also be advised that various vector drawing applications like Illustrator, CorelDRAW, Affinity Designer, Vectornator, etc do not have 100% feature overlap with each other. There is a lot of unique things Adobe Illustrator can do that can't duplicated so easily in rival software. There are examples going the other way too (I can name a few regarding CorelDRAW). Anyway, the point is you need to be careful what features and effects you use in your project if you want the file imported into other applications as accurately as possible. I can see some pretty wacky things happen from time to time when bouncing artwork between Illustrator and CorelDRAW.
Files saved in PDF format are technically not meant to be edited further, but other graphics applications can import PDFs with varying degrees of success. Illustrator can save PDF files with Illustrator editing left intact. Such PDF files may import more successfully into rival graphics applications.
Save your files on a local disc rather than in the cloud (or save in a different cloud than the one run by Adobe). Be careful what fonts you use in your project. If you lean heavily on typefaces synced via the Adobe Fonts service you'll either have to maintain your subscription to use those fonts or buy copies of those fonts outright from other font stores like MyFonts. That can get really expensive. One exception on the fonts front is Google Fonts. Adobe features a number of those in its service, but Google's fonts can be downloaded free from their own site.
Illustrator can save PDF files with Illustrator editing left intact. Such PDF files may import more successfully into rival graphics applications.
The "Editing capabilities" do not change anything in the PDF part of the file. It's the PDF part of the file that the other apps use. Some applications might even be irritated by the ambedded Ai file, which is there to provide the "editability"
CorelDRAW can open native ai files, but only up to version CC2019.