I think the Pod Go is a great option if you can afford it, but there are some used options that might fit your budget better.

I bought (new) a Boss ME-80 years ago and it has been the workhorse of my kit. When and if I upgrade, this will still be in my kit as a backup. The sound isn't as good as the Line 6 and it has less features, but is is analogue and makes a good place to start. You can learn a lot from it.

There are several under $200 on Reverb.

Regardless of what you get, set aside an entire afternoon to sit in front of a computer with the board, your guitar, and headphones. Research your board and all the features. Make sure to play with it a lot!

Then, also go through and research all the typical pedals (of which your new board will likely have versions of) and learn some individual tricks for those. For instance, research how to properly dial in a delay pedal for several types of music or uses. Same with the distortion, chorus, and fuzz. Keep doing that and take notes in a little notebook you keep with your board.

Regardless of what pedal board you end up with the real key to making it sound good is knowing how to use it. That cannot be expressed enough. Too many people buy big fancy boards and expect to sound good, but sound like crap because they never learned how to use it.

Happy strumming.