Civic b20b 16a swap coolant issue

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Fan never turned on when I idled it and coolant came that's probably the issue
With a cooled down motor:

Take radiator cap off
Start car
See if the radiator will take any coolant
Make sure you can see (roughly) the coolant level
Let it idle for a while (this should take 20-40min)
Periodically check temp gauge
See if the thermo opens (by looking at coolant level in rad)
Add coolant if level drops when thermo opens
Fan should come on when thermo opens

If the car heats up.....

Thermo may not be opening. You can check the thermo in a hot glass of water or buy a new thermo (not sure if you've already done that). They're mechanical and operate based on temp. They're designed to stay open when they go bad but I figure it's possible to stick closed.

Or a clog in your coolant system

Or.....the water pump is toast. Take timing cover off and visually inspect for leaks around water pump. Driver's side and it runs on the timing belt.

Come to think of it....a new timing belt and water pump is not a bad idea....depends if they guy before did it or not. Some guys continue using parts by scavenging off blown engines.
Well I opened the rad cap just now, and coolant is literally to the top on the radiator when I had it running before the top coolant hose was hot and I believe the bottom was too, but I'll start it up and try it out
So can never came on, temp gauge never went past half and coolant never really boiled out, but it looks like It was burping, the bottom line never got hot until it started to burp both lines are hot...the overflow doesn't look like it even went down maybe a little...
110% need to be getting fan on but im not leaning torwards thermostat sticking closed they have been fail save to stick open when fail for over 15 years , im leaning torwards if headgasket issue from the b20v setup not done correctly if the fans dont fix it
I suspected the heads at the beginning when I wasn't sure about the fan so I checked oil and coolant but they're both proper color, haven't seen anything out of the ordinary, no smoke or anything and I had never seen the fan turn on, so hopefully it's just that
should be a standard 15A blade fuse
there is probably a spare one in the interior fuse box

unless its the actual relay you are missing
in which case you will probably need a proper one
but could likely get one on the cheap at a pick and pull
Check some wiring at the fan. Does it look tampered with? If it looks fine, toss a 15A in the fuse holder and see what happens. If fan still doesn't come on, check fuse and, if it's still good, put it back and try to follow the procedure I linked for you.
It's been a couple days, been busy. Turned out i never had a relay, I ran it that day anyway and got some good driving in, never overheated or lost coolant so definitely a fan issue, she's pretty shaky and sounds like she wants to fall apart inside but it's got speed that's for sure!