bash: creating an xls/csv - excel

Question

Found these answers but from these it is not clear to me how to simply create excel sheets.
These two marked as answer do create a sheet out of a given txt BUT the data in the two txt columns get inserted in a single column in the table created:
How to convert a text file into excel in bash or perl
As if the tab-delimiter didnt work.
This answer does the same to me:
How to write text file data into same cell of excel using bash
This one is too complicated for an amateur:
Paste output into a CSV file in bash with paste command
I just am not able to decipher and simplify the stuff.
This does the same - columns end up merged in the first one:
#!/bin/bash
while read value; do
echo "$value"
done <tabulka.txt > test.csv
May I ask for a simple way to put data to an xls/csv? Im not really a bash expert, just an engineer forced to work with it. Thanks!
EDIT:
sample textfile as requested (tab as delimiter):
header1 header2
aaaa 1.0
bbbb 1.1
cccc 1.3
result:

Answer 1

Ok, so first step is to convert .txt to .csv. You don't provide your input data, so it is hard to see how you want to split it. If we assume, that your input file has fairly regular structure and you want simply replace " " to ",", you can do it like this. (But it would really be better if you clarified your question with sample data.):
#!/bin/bash
while read value; do
echo "$value" | tr "\t" ","
done <tabulka.txt > test.csv
The second part is explained in the link you pasted - Paste output into a CSV file in bash with paste command
Excel can read the csv file ( as can libreoffice ). This works for me.
libreoffice --calc test.csv
If your file is in any way irregular it's not possible to guess, you have to show it.
Edit: I was writing my answer, when you posted your input. So I'm editing it to reflect, that you use tabs in the input.