Can i get Merlin?

Assuming Merlin is released in January, you have about a 43.39052% chance of getting Merlin. But that's just a wild guess.

Maybe if you are lucky you will be able to get him. In my opinion is a better idea try to take another 30/60 s.q.
Usually I'm very unlucky and I wasn't able to get Jean alter with 50 summons.

Since it's chance based you can get him with one ticket or not with 1000 SQ, but best ammount to get 5* is something around 420 SQ

If your lucky enough, I guess you have a good chance. (in my old account, i have 300 sq and didnt get Jalter) anyway just dont roll all at once.
Now, I do 10x roll per day on a rate up that i like.

As an F2P, it's a pretty reasonable amount of SQs.
Yes it's worth the shot and i hope you're lucky.
Because luck can't be calculated.
Just save for a little more and focus for Merlin, your main target.

Your chances are not that bad,just hope you're lucky enough to get him

Depends on how good your luck is, how much quartz you saved up, and how willing you are to whale.

The math is pretty easy.

You have a 1% chance of getting a 5* per pull. That means that you have a 99% of *not* getting a 5*, and in N pulls, you have a (0.99)^N total chance of not getting a 5% (and, hence, a 1 - (0.99)^N of *getting* a 5*). If you roll only on single rate-up banners, then the chance of getting the rate-up 5* servant is 0.7% per pull (and 0.3% of getting spooked with some other random 5*).

So, 120 SQ + 15 tickets = 55 rolls. (Doing single or multi-rolls doesn't matter.)

1 - (0.99)^55 = 42.6% chance of getting *any* 5* servant
1 - (0.993)^55 = 32% chance of getting Merlin

You need 99 rolls for a 50% chance of getting Merlin. Whether roughly a 1 in 3 chance is a "good chance" or what's a reasonable amount to gamble on getting him is up to you.

Just remember the first rule of gacha: Decide before you start rolling what your limit is in how much you're willing to spend on chasing something. Stop when you hit that limit.

Most probably, no. Reasonable would be something like 500-600quartz.

Even with 600, 1 of every 4 people will fail. The rates are brutal, just assume you will not get him and remember that 200 quartz are worthless the next time you consider paying them 80$ for 167 quartz.