If you're still using the "free sample" filament that was supplied by Tevo, do yourself a favour and buy some good quality filament. I use eSun PLA+ myself (plus a little XD Filament PLA), but you'll find lots of good filament recommendations online. The Tevo supplied free filament is often pretty poor quality stuff, and can cause you more problems that it's worth, when you trying to get your printer tuned in.
For hot end temperature, follow the filament manufacturer's recommendations. Even though lots of different manufacturers sell PLA, they often have variations of different additives which they use to try to make their filament better than the opposition's filament. Best recommendation is to use the hotend temperature for your filament that is in the middle of the range specified by the Filament manufacturer - then if you need to, fine tune the hotend temperature.
For eSun PLA+, and XD Filament PLA, I don't use Bed Heating at all - UNLESS, I getting warping of the print job, in which case I'll set the bed temperature about half way between the room temperature and the maximium bed temperature recommended by the filament manufacturer. I find I need more bed heating for PLA in winter when the temperature in my workshop can drop to zero centigrade overnight, but in Summer, or whenever the room temperature is over 25 degrees, I usually don't need any bed heating with PLA.
For further diagnosing 3D Printing issues, try these two links for lots more guidance:
1) https://www.simplify3d.com/support/prin ... eshooting/
2) https://all3dp.com/1/common-3d-printing ... er-issues/
The first link is published by Simplify3D, and the solutions to the print issues refer to settings in Simplift3D Slicer - but you can usually translate the suggested fixes to whatever slicer you're using. I use Cura 3.0 and have been able to translate the suggested fixes to setting changes in Cura. Hint: Make a record of all the slicer setting changes you make, and why, in case you need to back out of any of them.
The second link is more generic, but equally useful.
I hope that info helps,