I've probably tried a dozen or so different brands of PLA on my Prusa MK3s. Some I love, others I like, and still others are trash. My personal favorite brands based on quality, consistency, ease to work with, and color are as follows:
#1 | Prusament (By far #1 for me. Cheapest if you order in increments of 2 spools at a time due to shipping) | https://shop.prusa3d.com/en/42-prusament?orderby=name&orderway=asc
These you can all get on Amazon
#2 | 3D Solutech
#3 | Gizmo Dorks
#4 | Hatchbox
#5 | Amolen
#6 | eSun
As a point of reference, I'm a hobby printer who also creates and sells 3D mods (mostly pinball, but not exclusively). I currently have about 20 different rolls of filament in my cabinet that I use for various things, I can't guess how many dozens of spools I've gone through over the last several years.
However, my opinion is just that. I'm not providing any objective analysis of what filament is best and why. All I know is that I want something that prints consistently, results in high detailed prints, has good opaque color (unless I'm wanting translucent), is of consistent quality and sizing, etc. Also, if you want "clear" PLA (really a misnomer) I've tried 6 or 7 different brands/kinds. By far the clearest PLA I've found is 3D Solutech's "Premium PLA" (not their standard PLA). Most all clear PLA filament is milky, but this stuff as very clear on the spool and still pretty clear in thin layers.
Also, the common wisdom is that PETG is stronger than PLA. This has been proven to be false in numerous comparison tests. There are multiple factors related to strength including infill, perimeter layers, grain direction related to stress, etc. What PETG does have, however, is a much higher melting point so it is good for objects that will be in hotter use environments before it softens (ABS is even more resistant to heat, and there are even other blends beyond ABS for stronger mechanical parts). PETG also does have more flex. However, depending upon just how much flex you may need a PLA model printed with the right infill can give you plenty of flex. Don't get me wrong, PETG still has it's place and is a great material. It is a little harder to work with (primarily nailing down the settings for a good first layer), sticks to the bed a lot more so can be difficult to release, etc.
90-95% of what I print is PLA, 5% PETG, and the occasional ABS part. PLA is by far the easiest material to work with when you are learning, so I'd by a couple of common colors (black, silver, white, whatever) and start learning how to print 3D objects.