TYPO3 Update to 8.7 Template not working - typo3

Question

I try to update an Typo3 Installation from 6.1 to 8.7 LTS but i dont get the templates working.
What i did so far:
Updated the core to 6.2 -> 7.6 -> 8.7
Updated all the Extensions as possible
The old installation used Fluid Pages Engine but this is not available for 8.7. As far as i understand it, fluid is now included in typo3?
Backend is working so far. I can administrate users, Pages and everything i looked at. However, when i call the frontend, i get an Exception:
#1294587217: The page is not configured! [type=0][]. This means that there is no TypoScript object of type PAGE with typeNum=0 configured.
TYPO3\CMS\Core\Error\Http\ServiceUnavailableException thrown in file
...\typo3_src-8.7.10\typo3\sysext\frontend\Classes\Controller\TypoScriptFrontendController.php in line 2487.
I tried the solution from the wikipage and replaced the "setup"-Template information
<INCLUDE_TYPOSCRIPT: source="FILE:fileadmin/typoscript/domain.ts">
<INCLUDE_TYPOSCRIPT: source="FILE:fileadmin/typoscript/typoscript.ts">
page.stdWrap.parseFunc.short.i3 = <span style="text-transform:normal;">i3</span>
with
# Default PAGE object:
page = PAGE
# Define output for typeNum=0, the default type.
page.typeNum = 0
page.10 = TEXT
page.10.value = HELLO WORLD!
Then i see "HELLO WORLD!". Now i stuck: what do i have to do to get the "normal" template working?
Thanks in advance

Answer 1

TYPO3 7 and 8 both include the FLUIDTEMPLATE Typoscript object, but EXT:fluidpages is an external extension mantained by the fluidtypo3.org team.
As you wrote:
# Default PAGE object:
page = PAGE
# Define output for typeNum=0, the default type.
page.typeNum = 0
page.10 = TEXT
page.10.value = HELLO WORLD!
You are defining that the PAGE object will contain only that simpe TEXT object.
A "minimum" configuration to use the FLUIDTEMPLATE object would be:
page = PAGE
page.typeNum = 0
page.10 = FLUIDTEMPLATE
page.10{
templateName = Default
layoutRootPaths {
0 = Path/To/Your/Layouts/
}
partialRootPaths {
0 = Path/To/Your/Partials/
}
templateRootPaths {
0 = Path/To/Your/Templates/
}
}
which means that you are using an Default.html template
to use different templates, you should also configure some backend layouts; assuming that you are using the database to store them the previous code could become:
page = PAGE
page.typeNum = 0
page.10 = FLUIDTEMPLATE
page.10{
templateName= TEXT
templateName.stdWrap {
cObject = CASE
cObject {
key.data = levelfield:-2,backend_layout_next_level,slide
key.override.field = backend_layout
default = TEXT
default.value = Default
//these are the IDs of the backend_layout records in DB
1 = TEXT
1.value = Default
2 = TEXT
2.value = Home
//add other values
}
ifEmpty = Error
}
layoutRootPaths {
0 = Path/To/Your/Layouts/
}
partialRootPaths {
0 = Path/To/Your/Partials/
}
templateRootPaths {
0 = Path/To/Your/Templates/
}
}
See also: https://docs.typo3.org/typo3cms/TyposcriptReference/ContentObjects/Fluidtemplate/Index.html
If you need further help I could suggest you to join the typo3 Slack channel (subscribe here: https://forger.typo3.com/slack) and join the typo3-cms channel and the fluidtypo3 channel.

Answer 2

I think your typoscript file is not included in ROOT Template.
First of copy all typoscript in the typoscript.ts file and paste in the setup.ts in ROOT Template and after check the frontend. If every thing is fine then definitely your typoscript is not included on ROOT template and if this is not working then some mistake in your typoscript object