Four starting points, four routes
The question sounds simple but has four different answers, depending on what you already have. A finished Word file needs a different route than a stack of photos or text that has not been written yet. Pick the wrong one and you end up with broken formatting or a file ten times larger than it needs to be.
Route 1: From a text document
If the content already exists as a Word file, converting is the direct route. Word to PDF carries over fonts, paragraphs and page breaks.
One thing people miss: unusual fonts installed only on your own machine can look different on the recipient's screen. If it matters, stick to common fonts. The same applies to spreadsheets via Excel and slides via PowerPoint.
Route 2: From images
Photos of a receipt, snapshots of a contract, scanned certificates: JPG to PDF turns images into a document. Order matters, and you set it before saving.
With phone photos, take a second look at the file size. A modern phone produces several megabytes per shot. Ten of those make a PDF no mailbox will accept. Compress PDF before sending.
Route 3: Type the text directly
Sometimes no document exists yet. A short statement, a note, a one-page letter: that needs no word processor. With Create PDF you type the text, pick the page format and download the finished file.
If the text already sits in a plain text file, TXT to PDF gets you there. It also lets you switch the character encoding, which decides between readable and garbled on older files.
Route 4: From a web page
An order confirmation in the browser, a booking overview, an article worth keeping: HTML to PDF captures it as it appears.
What is left to do
A freshly made PDF is rarely ready to send. Three questions are worth asking:
Is the file too large? Anything above 10 megabytes gets awkward for email. Compressing usually settles it in one step.
Should some parts stay private? Account numbers, dates of birth, addresses. Making them unreadable takes more than a black bar on top. The redaction tool actually removes the text from the file.
Does the document need protection? A password can be added afterwards with Protect PDF.
In short
The right route depends on what you already have: a text document, images, plain text or a web page. After that, check file size, sensitive passages and protection. Every step is free, needs no account and runs in the browser.