Because you are a beginner, I'd recommend you TRY before you buy anything because you probably don't know what you like as far as rod action...
In today's world, there are true-to-weight (TTW) fly lines that weigh right in the middle of the recommended range for their size and heavier fly lines that can be as much as a half to 1.5 times heavier yet still be labeled as the same line weight...
...for some reason.
For example:
Your rod is sold as a 4wt and a TTW 4wt line weighs 120 grains. An example of TTW lines are Cortland 444 Peach, 406 Fly Lines and Sci-Angler Mastery.
BUT, you may NOT like the way you rod feels with a 120 grain line...
Maybe you'd like it better with a 126 grain 4wt line like a Rio Gold or Sci Angler GPX or even a full size heavier line like a Elite Rio Grand 4wt at 140 grains.
The problem is, you won't know until you try at least ONE line of a known weight on YOUR rod as a benchmark.
If I was you, I would seek out a friend or fly shop that has some fly lines on reels to test out. Ideally a TTW 4wt line & a TTW 5wt line and try both to see what you like. If the TTW 4wt feels too light and the TTW 5wt feels too heavy, try half size heavier options and dial it in from there.
Even if the person or fly shop doesn't have TTW lines, as long as they know the brand and size you can get an idea what weight fly line works for you and your rod.
You might even want to bring along any bigger, heavier or more wind resistant flies you plan to throw because you may discover you like a certain weight line for trout fishing and a different line weight for warm water.
THEN decide what line at that/those weight(s) has the other features you think you'd like in a fly line...
...and it you did your testing at a fly shop, buy the line(s) from them.
It wasn't always this hard to match a line with a rod but, you said you want to get ready for next spring so you have plenty of time to experiment with lines beforehand.
What you don't want to do is spend money on a recommendation and find out it doesn't work for YOU.
Good luck!!