My first drawings of characters and comics I did in pen. I did not do an underneath sketch I just went straight for the drawing with pen? Idk why i decided to do that lol, I still sketch that way too, with just a crappy ballpoint or sometimes a nicer gel pen, the energel’s are nice and smooth and come with affordable refills! Also I can give the empty cartridges to my dad for him to use in his kit bashing diorama stuff, so I don’t mind going through a box of them.
For more finished works, I will draw a sketch underneath. For traditional I find that colored pencil looks better under marker, and I like the sketch showing through a bit. I tend use a burgundy or other reddish color for the sketch. I do not really erase, as I don’t find I need to, even when I do graphite drawings, it’s rare I erase anything? Digital I think I erase more, I guess with traditional I can’t erase because I draw so deeply into the paper. The line is there once it’s there
And to ink, I used to draw with either microns or Copic liners, but lately I’ve been using the gel pens because they feel better to draw with! And the tip is metal so it doesn’t fray, which works well with the pressure I put down on the pen when drawing. I would actually recommend gel pens instead of felt tip liners like microns, for anyone that has more of a heavy hand when drawing
When I draw digitally, I now use procreate but I used to use my cruddy economy Wacom tablet and photoshop. I prefer procreate, not because of the app itself, but drawing directly onto the image/screen works better for me than the separation between blank tablet and screen above. I use a variety of brushes, but I tend to pick ones that mimic traditional mediums. I use a lot of brushes from True Grit Texture Supply! Their brushes are available for multiple platforms too, not just procreate. The brushes feel very smooth too, and more natural to use.
Sometimes I use traditional line art, and place it in the drawing program, turn up the contrast in the image, then set its layer to “multiply” so that I can color underneath. That technique is super fun! 
I also just use MS paint, an emulated version of the 90s one, and find the simplicity fun and freeing! The lineart is how I start to the drawing, and slowly build up color around it, since there are no layers.