Go to the Safari menu bar CHANCH an select 'spelling' Check spelling as you type.
Not sure what CHANCH means? However, here's the path for Safari's spell check function:
Safari: Menu Bar>Edit>Spelling>
Check Spelling as you Type
Selecting this option puts a red broken underline under any words not matching the spell checker. To correct any misspellings,
Apple/Shift/: Keys or same path as above, except >Spelling. A panel box appears with various options including correction of the questioned word, or giving you the opportunity to ignore, or add that word to the spelling dictionary.