PC Upgrade Help for Lil Cousin, I'm Confused

my cousin is going to complete his 12th boards by the end of this march. so, i'm planning to surprise him with upgrades for his pc. he can barely game with his current setup that his parents got him during lockdown for online classes.

his current setup is an i3 9th or 10th gen with a Asus H310M E motherboard, GT 710, 8GB DDR4, 1TB HDD.

i'm trying to keep the processor and motherboard as it is and upgrade the rest of the items. things i'm planning to upgrade for him are a better GPU, odyssey G3 24" monitor, cool looking cabinet, 550W PSU, 512GB M.2 SSD, extra 8GB RAM.

my other two elder brothers and i are pitching in each 10k for this. so, the the overall budget is around 30k. so, help me decide the right parts. i'm thinking of RTX 3050 6GB for GPU as the gtx1650 is outdated. will it be compatible with the H310M motherboard? will a 450W PSU suffice or a 550W must? it's fine even if it slightly exceeds the 30k budget.

i need to upgrade the whole thing without changing the processor and motherboard. please help me out with some suggestions that are compatible for this.

edit : adding a pcpricetracker link. this is what i'm having in my mind - https://pcpricetracker.in/b/s/ef50a2ac-310c-46b6-865a-85f9156cc21f

please let me know if this would work or if any of you guys have better suggestions