two intervals after end of sentence


I put two intervals beweetn sentence as I think this is more pleasing to the eye. How can I replace the one intervals of an imported text with two?

Thank you.

You do not need to change any style or use regular expressions here.

Go to the top of your document and press Ctrl+H. This will open the Find and Replace dialog.
Ensure that ‘Regular expressions’ is not ticked.

In the Find box type a dot and one space.
In the Replace box type a dot and two spaces.
Click Replace All.
Close the Find and Replace dialog.

But be careful with shortcuts like “e.g.” or others.

Good catch @Hrbrgr - thanks!

Thank you for your suggestion and comments. However, I do not know how to make use of them with the exception that I leave one space even after the end of the sentence.

Trying to follow the answer: I go to Styles, select Text Body then Edit Style where I do not see a way to add two spaces. There is spacing above and below paragraph.

The first comment helped me. I tried to do it this way but went wrong in some way.

Thank you all.

This is not an answer to your own question. Please use the tool “add a comment” for posts of this kind.
Please make sure to use the term space only if you actually mean the non-printing little whitespace between two words (e.g.).
If you mean something concerning line wrapping (vertical positioning of text) there are two possibilities being different in a relevant way: NewLine (hard line break) and NewParagraph (paragraph break).
I feel sure you were talking of paragraph breaks.

I’m kind of a stumble - bum when it comes to regular expressions, and don’t have my cheat sheet handy, but I believe you can search for the dot character followed by only one space and an alpha character, then replace with dot space space same character.

===Editing due to the comment by @mikekaganski ===
Go to the final part which is about additional spaces.
To replace a single paragraph break by a sequence of two paragraph breaks, you need to use F&R with the option Regular expressions enabled. Enter the single character $ behind Find: and the sequence \n\n (4 characters) behind Replace:. Then order Replace All.
Be sure to understand that you will get two empty paragraphs for each single empty paragraph if there was any.
I do not know a way to double hard line breaks using F&R. The extension AltSearch can do that.
The standard way to get additional distance between paragraphs is to add a Spacing below paragraph to the used paragraph style. (Tab Indents & Spacing)

===See below===

If you actually want to get an additional horizontal space between sentences you need to identify the end of any sentence. Supposing the end of a sentence is marked by (exactly) one of the punctuation characters !.? you can search for ([!\?\.]) and replace with $1 with a space bhind the $1. However, you will then get from
He asked, "did you read it?" a He asked, "did you read it? " and this may not be what you want. Things get complicated at that point. ((!"|\."|\?")|[!\?\.]) can help.

I had made the same mistake, and had do remove my answer afterwards. The OP wants two space chars after each sentence, not two paragraphs after each paragraph…

You really sure? I’m not.

After all I’m at least sure to have wasted time again. A solution by F&R seems too complicated, imo.