These are my goto throw away synthetic brushes. Royal Brush Taklon Hair Classroom... https://www.amazon.com/dp/B002KQYC74?ref=ppx_pop_mob_ap_share
You definitely don't need expensive brushes. I have a few and don't use them that often. I use these for 95% of my painting. https://www.amazon.com/dp/B002KQYC74?ref=ppx_pop_mob_ap_share
Get a cheap set of army painter paints and wet pallette. https://www.amazon.com/dp/B000C18GTE?ref=ppx_pop_mob_ap_share
https://www.amazon.com/gp/product/B002KQYC74/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&&psc=1
round ones are useful; flat ones less so, but hey, still good value
Representative examples of what I use:
Synthetic Brush Pack: https://www.amazon.com/gp/product/B002KQYC74/
Winsor & Newton Series 7: https://www.amazon.com/Winsor-Newton-Kolinsky-Sable-Watercolor/dp/B0013E68T4/ (i only have this one brush, I don't use it except for layering)