for me i donate to https://protectavolunteer.com/ who send the funds directly to soldiers, weapons to ukraine who have campaigns like https://weaponstoukraine.com/en/kampane/sos

SOS Kyiv – Emergency Fundraiser for Generators and Backup Batteries

and UFL Robin https://www.reddit.com/user/UFL_Robin/ who does weekly raffles like this one that just ended:

https://www.reddit.com/r/ukraine/comments/1qjvk1q/about_7_hours_left_for_a_shot_at_three_packages/

they literally post videos and photos showing the goods being received like

https://www.reddit.com/r/ukraine/comments/1qjxgmj/tempest_group_of_3ab_and_fluffy_boy_downie_thank/

this is about as close to the front line i can get without being there

irl i don’t have time to do charity work so before ukraine i would donate to a homeless shelter and climate change charities, I try to buy australian or european where I can, avoid american/chinese, and have solar panels/solar battery/ev and heat pump, i also export a big chunk of battery power every night during 5:30pm to 7:30pm to reduce demand when fossil fuels are being used the most, it takes about a ton per year of co2 off

tldr i don’t have time for charity work as im already pretty busy irl similar to you so i try to make up for it by having my donations go as far as possible and things i spend money on make the biggest impact