welcome to the forums and vg!
for me, it took a month to familiarize myself with everything with very ligtle moba experience (played LoL like years ago for a week), by this time i was able to learn stutterstepping (find other guides for this bc i can’t explain it well, but it makes your dps go up.), what the items do, and my playstyle.
every week, test out the heroes from the weekly rotation and see who you like. this’ll help you develop a hero pool, then find who you like the most in your hero pool (for now you said koshka) to practice them more.
for beginners, i think these are the easiest heroes to learn for each role (in 5v5)
mid (usually a mage or a burst hero like kestrel): skaarf
bot (marksmen): gwen and ringo
top(tanks or more mages): grace, glaive, joule
jungle (honestly diverse, but usually either provides some utility or can assassinate enemies more easily): koshka glaive grumpjaw
captain: ardan lyra catherine
(note my list is just my opinion, i could be missing some others or wrong about heroes i put there)
always read patchnotes and forums every update! even if youre not familiar with everything right now, the numbers for balance will give you a sense of who’s weaker and who’s stronger
some people like watching youtubers or streamers play vg and learn from them
learn how to play your characters first, then move on to figuring out how to build w/o blindly following the recommended, then practice mechanics.
have fun! people in the forums are very kind most of the time when it comes to helping people
if you see anyone pinging you in a way that seems rude, muting them (in the scoreboard, the social part, just tap the chat bubble next to their icon) really helps. if you don’t enjoy the game, take a break so you don’t burn out