How do i know if the Injectors is bad?

With misfires on two adjacent cylinders I would do a compression test before going any farther. Not uncommon for a head gasket to fail between two cylinders. The gasket is very narrow at that point and there are no coolant passages so a failure will show as both cylinders misfiring as the compression passes between them.
https://www.2carpros.com/articles/head-gasket-blown-test/
Will show you how to do the test. Doing a leak down test using compressed air would also show if it were the problem. You would put air into cylinder 4 with it on TDC and have air exiting cylinder 3.

Cylinder #1,195psi
Cylinder #2,190psi
Cylinder #3, 185psi
CylinderCylinder #4,190psi
I done replaced the coils, spark plugs, fuel injectors and camshaft position sensor and still have a misfire on #3 and #4 cylinder can you tell me is causing of the misfire?

Well with those numbers it shouldn't be compression as the cause. Because the coils share so many circuits it shouldn't be the powers and grounds, however I would double check that you have battery power at the Brown wire to each coil, and a ground on the White with black wire. From there I would connect a test light to battery power and see if the light comes on when held to the Green wire on the coils. The various greens are the trigger wires for the coils. If the light flickers on with the engine running the ECU driver circuit should be working. The next step would be testing the injectors, for that a set of noid lights would be handy, many parts stores have them as loaner tools. They just clip in place of the injector and flash if the injector circuit is operating.

OK I went back and looked at all the other threads you have started on this. Looks like you said the injector pulse was confirmed earlier, but that it would drop out after a time and misfires. You changed a lot of parts and now say that the exhaust is glowing red hot. Generally that means either the exhaust is plugged (which would cause a misfire) or it is running very lean. With the earlier issue of the dropping injector pulses and other problems but with good compression in the cylinders I would look at the ECU. Especially with the dropout signals. Also could you please not start a new thread every time, it makes it hard if someone else were to try to search for your problem in the future. You can just log in and add the information to the same thread on the Camry. Thank you.

I have battery power at the brown wire to each coil.i did a retest with the test light and the light come on the test light flickers on with the engine running, the noid light flash when engine running. i remove the valve cover and check for slack between the camshaft sprocket there was about 3/8-inches of slack.

If the noid light is flashing all the time when connected to the injector then the control pulse should be there, it's if it flashes, then goes out then flashes again that would make you worry, that would mean a driver issue in the PCM. But constant flashing should mean it's likely a bad injector. A simple way to test is a injector balance test. For that you need a scan tool that can trigger the fuel pump or a jumper for the pump relay so you can run the pump. Then a fuel pressure gauge attached to the fuel supply rail, and an injector pulse tool. What you do is to connect it all up. Now you actuate the fuel pump to get full line pressure say 50 psi. Now you use the pulse tool to activate an injector. Say No. 1, and watch the pressure drop as the tool pulses. You then repeat that for each injector. You get done and find that 3 injectors start at 50 psi and drop to 35 psi but the last one only drops to 44 psi, that injector is faulty and could be causing a lean condition and the misfire. OR it might drop to 20 psi and the resulting rich condition causes the misfire.

i replace all 4 injectors.

Please go over this guide.

https://2carpros.com/articles/how-to-test-a-fuel-injector/