You spent your early resources wrong. Here is the fix

The first three days refund

Anything you invest in a Pokémon during your first three days can be dismantled at a full refund. Use that window to experiment; commit only after you know what your carry is.

Star up in the right order

For ordinary SSR and the pseudo-legendaries you can catch in the wild, push the juvenile form to the star cap of its stage and then evolve. That saves a chunk of shards versus evolving first. Do not chase high stars on a fresh account; get the carry to a usable star level and move on.

Do not obsess over IVs yet

IVs mostly come from the nightly moon dungeon, and buying the daily attempts is the fast route. Every stat caps at 31, but an average of 28 across six stats is enough to clear content. Save the 6V attempt for when you have crowns and a few thousand capsules.

Quality, EVs, friendship

Quality comes from charm stones and charms; tiers one and two are handed out, tier three is a shop purchase, tier four is a dungeon farm or a discount wait, tier five belongs on a weekend double-drop. EVs cap at 252 per stat and 510 total. Friendship arrives from nutrient drinks and pays out at 99, 199 and 255.

Breaking a wall

Level-50 walls like Professor Oak fall to a sleep move from Butterfree or Toedscruel. Gym progress tracks your level, so as long as investment keeps up, PvE rarely blocks you.