Speaking only on the watercolor side of things!

Paper can be very subjective... but this is my absolute favorite. It's a bit pricey. However, this paper hardly buckles at all when I use it and it dries completely flat - Arches and all the other popular ones usually require me to iron the paper after, and I've really just stopped using anything else. It also takes a lot of abuse. The pads are good, but there are also large sheets you can cut down to whatever size you like.

https://www.dickblick.com/products/laquarelle-canson-heritage-watercolor-pads/ (You can checkout with Amazon using Dicks and their prices are often much better)

Here are some brushes I've picked up that I really like.

https://www.amazon.com/gp/product/B007PMP5DS/ref=oh_aui_search_detailpage?ie=UTF8&psc=1 This one is great for details, and I prefer it greatly over typical script liners

https://www.amazon.com/gp/product/B00512C1VS/ref=oh_aui_search_detailpage?ie=UTF8&psc=1 Just an overall great brush. It's really floppy so takes some getting used to if you haven't used one like it before.

https://www.amazon.com/gp/product/B004BNCNCK/ref=oh_aui_search_detailpage?ie=UTF8&psc=1 Similar to the first brush I listed. Great for tree branches etc

https://www.amazon.com/gp/product/B000H86SUQ/ref=oh_aui_search_detailpage?ie=UTF8&psc=1 Just some cheapy hake brushes. I These are super duper soft and great for laying down washes.

And with all those brushes... https://www.amazon.com/gp/product/B0027AEANE/ref=oh_aui_search_detailpage?ie=UTF8&psc=1 (it's like .40 cent cheaper on Dicks)

And just some other random things I have bought in the past two years that I absolutely love/would buy again

https://www.dickblick.com/products/gatorfoam-board/ These are great to tape or stable to, and last MUCH longer than Masonite boards

https://www.amazon.com/gp/product/B000WS3CC8/ref=oh_aui_search_detailpage?ie=UTF8&psc=1 I hate how plastic palettes make the paint bead up. Porcelain doesn't allow that to happen and doesn't stain. I love this little tray, need to get more.

https://www.dickblick.com/products/escoda-perla-toray-white-synthetic-round/ These are really nice brushes

https://www.dickblick.com/products/grumbacher-goldenedge-round/ As are these

https://www.amazon.com/gp/product/B0077RHJSK/ref=oh_aui_search_detailpage?ie=UTF8&psc=1 These are great white pens to add details after paint has dried

This https://www.amazon.com/gp/product/B004XL1D26/ref=oh_aui_search_detailpage?ie=UTF8&psc=1 + https://www.amazon.com/gp/product/B00ELGCSU4/ref=oh_aui_search_detailpage?ie=UTF8&psc=1 this is the best method for applying masking fluid i've found (preserving the white of the paper)