Boys, what can I/can I not comment on your/their profile pictures?

[Teressa]

Hi! I am 16. Often my guy friends that I don't know very well/just met/don't talk to often change their profile picture to something really cute/handsome/gorgeous and I never know what to say so I just end up liking it. I don't want to flirt or hint that they are more than a friend, but I want to complement them just like I would with a girl. What are some acceptable complements? Where do you draw the line between friend complements and flirt complements or should I just like?

[Connor]

Put that it's a nice picture.

[Frank]

in my opinion just be open. and put something nice. dont over do it and say like omg you're so hot. dont be afraid to post what pops to your mind. they will like the attention. not necessarily will hint that you might have some time of crush or feeling towards them. sorry i cant be of any further help.