Any good wads for Zdoom that I can try?

Surprise me, they  can be silly i'm just looking for one to have fun in.

There was a similar thread about this just recently.  There might be some good ideas in there. 

It is a known scientific fact that there are more (G)ZDoom WADs than there are species of lizard, and new ones appear at roughly the same rate.

In all seriousness, if you want something different, try out my TC WAD, Fury's Sky. Turns GZDoom into a flight game a la Rogue Squadron.

Other mods I've liked are Russian Overkill, Demonsteele, Metroid Dreadnought, Doom RPG, and Legendoom

Ah geez, no one mentioned Shadow of the Wool Ball? That's a fun and cute one that you can beat with ease. https://www.moddb.com/mods/shadow-of-the-wool-ball

I'll also pimp my own community project, Doomed in Space. Pretty much a classic Doom mapset with a sci-fi twist, though there are ZDoom elements such as railguns and 3D bridges.

Whilst not DooM related (but was built for ZDooM) is XUMP (Hexen Upstart Mapping Project). It's a fairly fun set of maps with an interconnecting HUB.

ᴀɴᴅ ɪ ᴍᴀʏ ᴏʀ ᴍᴀʏ ɴᴏᴛ ʜᴀᴠᴇ ᴀ ᴘᴀʀᴛ ɪɴ ɪᴛ.