Edit to prevent accusations and to not confuse people who can't add context to a picture.
So first response will be:
What type of ammo are you trying to bounce, side scraping and angling yourself is the future. Even if you have no building to hide your lower front plate, angling it is still better than not. Try to encourage your enemy to panic or fire pre-emtpively into your nice angled or slopey armour.
For HEAT, you need to try and encourage the enemy to shoot into spaced armour and tracks, avoid presenting flat surfaces wherever possible! You won't achieve this all the time but it is doable. One mod i used when i set on the journey to improve was something similar to this but far more basic:

That's the basics and I apologise for those but in case anyone who didn't know.
Next, for things like your type 5 heavy, first thing, is there a rush to engage him? Is there a reason you REALLY need to show a flat panel or more of your tank to fire before he does? Even angling against HE will mitigate than if you give a nice flat panel like the front of your turret.
Against big scary tanks, try not to get yourself into a position where they can fire freely at you from range from relative safety, not always possible, but it should be an attempt regardless.
Something I feel many people don't do anymore and I used to see it all the time, do not be afraid to wiggle your tank, don't be afraid to rock back and forth with your vehicle and make it harder for the enemy to find that perfect weak spot, make it harder for them to hit your turret by wiggling some more or trying to put your barrel in the way. It won't work every time but the attitude helps and even 1 round stopped is better than not trying at all.
As mentioned above, WoT can be about patience and E100 is a tank that excels in patient play, solo yolo hero and you'll be free xp. But if there's no urgent need to advance, just wait, shoot at another target. If you can hold that corner for your team vs multiple enemies you're doing more for your team than dying by getting off 1 shell of damage and taking 1-6 in return.
The thing with tanks like the E100 and other vehicles is they were introduced in a time of very different play styles of the community, they can still work, but they are not as strong as they used to be. These days mobility is a greater commodity than armour and alpha. This is not the case for all maps, and your E100 can still have an outstanding game if you stick to your tank's strengths.