raten
to guess
To make an assumption about something without knowing the answer for sure.
Ich weiß die Antwort nicht, ich kann nur raten.
I don't know the answer; I can only guess.

to guess / advise
Loading your saved state.
to guess
To make an assumption about something without knowing the answer for sure.
Ich weiß die Antwort nicht, ich kann nur raten.
I don't know the answer; I can only guess.

The meaning of 'raten' (to guess / advise) depends strongly on the sentence structure. If the verb stands alone or with an accusative object, it means 'vermuten' (to guess/assume). However, if it is followed by a person in the dative, it means 'empfehlen' (to recommend/advise).
Rate mal, wen ich heute getroffen habe!
Guess who I met today!
The verb 'raten' (to guess / advise) is the root of the nouns 'der Rat' and 'der Ratschlag'. Both mean 'recommendation/advice' and help you remember the second meaning of the verb.
Mein Vater gab mir den guten Rat, immer ehrlich zu sein.
My father gave me the good advice to always be honest.
When 'raten' means 'vermuten' (to guess/assume), it is often used in fixed expressions. Examples are 'richtig oder falsch raten' (to guess right or wrong), 'ins Blaue raten' (to make a blind guess), or in the prompt 'Rate mal!' (Guess!).
Er wusste die Antwort nicht und hat einfach nur ins Blaue geraten.
He didn't know the answer and simply made a blind guess.
When you give someone advice, the person is always in the dative. The recommendation itself often follows as a subordinate clause with 'dass' or as an infinitive construction with 'zu'.
Ich habe ihm geraten, sich für den Job zu bewerben.
I advised him to apply for the job.
to say
'sagen' and 'raten' can both be used when someone tells another person what they should do. The difference is in the focus: 'sagen' is more general and can also be a clear instruction or opinion. 'raten' means that you give a suggestion or recommendation, usually in order to help someone. Learners may confuse the words because in German you can say 'Ich sage dir, was du tun sollst' (I'll tell you what you should do) and also 'Ich rate dir, was du tun solltest' (I'll advise you what you should do). But 'raten' sounds less direct and more like advice.

Nach dem Gespräch rät der Arzt dem Patienten zu mehr Ruhe.
After the conversation, the doctor advises the patient to get more rest.
Die Lehrerin sagt den Schülern, dass sie die Aufgabe zu Hause beenden sollen.
The teacher tells the students that they should finish the assignment at home.