PLS HELP, MY MAC BECOME SLOW AND LAG WHEN CONNECTED TO WIFI :(

Hello, it's kinda weird.

not the CONNECTION got slow, but the MAC :(

I'm using MacBook Air 2019, latest macOS update, with large empty space.

When I connected to my house wifi, my Mac become very lag and slow. it takes much longer time to open apps. if usually it takes 2s to open an app. my Mac took more than 2 minutes just to open LINE APP.

And it only affected to downloaded app like chrome, Microsoft, LINE, iMovie, and Spotify. when I open that app, it took very long to open them. 2 minutes to open Line...

but I can open safari, notes, maps, mail, default Mac app as fast as normal.

The lag disappear when I disconnect the wifi. It's like the issue completely gone when I disconnect from the wifi. but it impossible to stay disconnected bus I need internet to do my study :(

I've tried to reset my network preferences (delete saved wifi, delete wifi-bluetooth-thunderbolt-etc than add it again.) I've reset my Mac using recovery mode -> erase disk, but it wasn't gone. sometimes the Mac become normal when I used other wifi like mobile hotspot. but it's very annoying that I get slow when connected to my home's wifi.

it started 1 month ago, I went out of my city, stayed at hotel, connected to wifi there. and when I get home. this issue happen :(

it's not like the wifi internet connection get slow, but it's the Mac get slow.

thank you for u guys help... :')