à & de after infinitives changing meaning

to persuade, convince (someone)

décider qqn à

to decide to

décider de

to ask (for permission)

demander à qqn

to ask (to do)

demander de

to play a game or sport

jouer à

to play a musical instrument

jouer de

to miss (someone)

manquer à qqn

to neglect (to do)

manquer de

to talk to

parler à qqn

to talk about

parler de

to think about (imagine)

penser à

to think about (opinion)

penser de

to benefit

profiter à

to make the most of

profiter de

to happen to

venir à

to have just (done)

venir de