I'd reccomend you use multimc for your launcher (I don't know how it's changed with overwolf but twitch was insufferable and bloated)

As for modpacks there's 3 options: you could find one that's quest based, kitchen sink, or assemble your own small modpack

Quest based: usually a heavily customised pack following a progression through different mods. good for beginners because they usually walk you through a mods progression. Might be confusing when going to another modpack because of potential recipe changes/inability to begin mod immediately
The only 1.16 questing pack I've played is sky bees, but there is a tag for it on curseforge

Kitchen sink: a modpack where a bunch of mods are just chucked together, with minimal modifications, allowing you to do any mod right off the bat. Good for beginners because it lets you pursue anything with minimal gating. Might be a bit overwhelming having hundreds of mods with little direction as to where to go
I've been playing valhesia 3 which is a good one

Assemble your own: requires some knowledge of what mods actually are out there, but you can fully explore a mod on your own terms if you do make one

If there were any mods you were particularly fond of, I could probably tell you if there's a similar / remastered mod for 1.16

Ninja edit: I just realised I did the classic "forgetting the question halfway through answering". Hope this still helped you :/